有没有一种简单的方法来检查.NET Framework版本？

问题是，我需要知道，如果它的3.5版本SP 1Environment.Version()只的回报2.0.50727.3053。

我找到了这个解决方案，但是我认为这将花费更多的时间，因此我正在寻找一种更简单的解决方案。可能吗？

这样的事情应该做。只需从注册表中获取价值

对于.NET 1-4：

Framework是安装的最高版本，SP是该版本的Service Pack。

RegistryKey installed_versions = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
string[] version_names = installed_versions.GetSubKeyNames();
//version names start with 'v', eg, 'v3.5' which needs to be trimmed off before conversion
double Framework = Convert.ToDouble(version_names[version_names.Length - 1].Remove(0, 1), CultureInfo.InvariantCulture);
int SP = Convert.ToInt32(installed_versions.OpenSubKey(version_names[version_names.Length - 1]).GetValue("SP", 0));

对于.NET 4.5+（根据官方文档）：

using System;
using Microsoft.Win32;


...


private static void Get45or451FromRegistry()
{
    using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\")) {
        int releaseKey = Convert.ToInt32(ndpKey.GetValue("Release"));
        if (true) {
            Console.WriteLine("Version: " + CheckFor45DotVersion(releaseKey));
        }
    }
}


...


// Checking the version using >= will enable forward compatibility,  
// however you should always compile your code on newer versions of 
// the framework to ensure your app works the same. 
private static string CheckFor45DotVersion(int releaseKey)
{
    if (releaseKey >= 461808) {
        return "4.7.2 or later";
    }
    if (releaseKey >= 461308) {
        return "4.7.1 or later";
    }
    if (releaseKey >= 460798) {
        return "4.7 or later";
    }
    if (releaseKey >= 394802) {
        return "4.6.2 or later";
    }
    if (releaseKey >= 394254) {
        return "4.6.1 or later";
    }
    if (releaseKey >= 393295) {
        return "4.6 or later";
    }
    if (releaseKey >= 393273) {
        return "4.6 RC or later";
    }
    if ((releaseKey >= 379893)) {
        return "4.5.2 or later";
    }
    if ((releaseKey >= 378675)) {
        return "4.5.1 or later";
    }
    if ((releaseKey >= 378389)) {
        return "4.5 or later";
    }
    // This line should never execute. A non-null release key should mean 
    // that 4.5 or later is installed. 
    return "No 4.5 or later version detected";
}

不知道为什么没有人建议遵循从微软官方建议的权利在这里。

这是他们推荐的代码。当然很丑，但是行得通。

对于.NET 1-4

private static void GetVersionFromRegistry()
{
     // Opens the registry key for the .NET Framework entry. 
        using (RegistryKey ndpKey = 
            RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "").
            OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
        {
            // As an alternative, if you know the computers you will query are running .NET Framework 4.5  
            // or later, you can use: 
            // using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine,  
            // RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
        foreach (string versionKeyName in ndpKey.GetSubKeyNames())
        {
            if (versionKeyName.StartsWith("v"))
            {

                RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);
                string name = (string)versionKey.GetValue("Version", "");
                string sp = versionKey.GetValue("SP", "").ToString();
                string install = versionKey.GetValue("Install", "").ToString();
                if (install == "") //no install info, must be later.
                    Console.WriteLine(versionKeyName + "  " + name);
                else
                {
                    if (sp != "" && install == "1")
                    {
                        Console.WriteLine(versionKeyName + "  " + name + "  SP" + sp);
                    }

                }
                if (name != "")
                {
                    continue;
                }
                foreach (string subKeyName in versionKey.GetSubKeyNames())
                {
                    RegistryKey subKey = versionKey.OpenSubKey(subKeyName);
                    name = (string)subKey.GetValue("Version", "");
                    if (name != "")
                        sp = subKey.GetValue("SP", "").ToString();
                    install = subKey.GetValue("Install", "").ToString();
                    if (install == "") //no install info, must be later.
                        Console.WriteLine(versionKeyName + "  " + name);
                    else
                    {
                        if (sp != "" && install == "1")
                        {
                            Console.WriteLine("  " + subKeyName + "  " + name + "  SP" + sp);
                        }
                        else if (install == "1")
                        {
                            Console.WriteLine("  " + subKeyName + "  " + name);
                        }

                    }

                }

            }
        }
    }

}

对于.NET 4.5及更高版本

// Checking the version using >= will enable forward compatibility, 
// however you should always compile your code on newer versions of
// the framework to ensure your app works the same.
private static string CheckFor45DotVersion(int releaseKey)
{
   if (releaseKey >= 393295) {
      return "4.6 or later";
   }
   if ((releaseKey >= 379893)) {
        return "4.5.2 or later";
    }
    if ((releaseKey >= 378675)) {
        return "4.5.1 or later";
    }
    if ((releaseKey >= 378389)) {
        return "4.5 or later";
    }
    // This line should never execute. A non-null release key should mean
    // that 4.5 or later is installed.
    return "No 4.5 or later version detected";
}

private static void Get45or451FromRegistry()
{
    using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\")) {
        if (ndpKey != null && ndpKey.GetValue("Release") != null) {
            Console.WriteLine("Version: " + CheckFor45DotVersion((int) ndpKey.GetValue("Release")));
        }
      else {
         Console.WriteLine("Version 4.5 or later is not detected.");
      } 
    }
}

不需要访问注册表的另一种方法是检查是否存在特定框架更新中引入的类。

private static bool Is46Installed()
{
    // API changes in 4.6: https://github.com/Microsoft/dotnet/blob/master/releases/net46/dotnet46-api-changes.md
    return Type.GetType("System.AppContext, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089", false) != null;
}

private static bool Is461Installed()
{
    // API changes in 4.6.1: https://github.com/Microsoft/dotnet/blob/master/releases/net461/dotnet461-api-changes.md
    return Type.GetType("System.Data.SqlClient.SqlColumnEncryptionCngProvider, System.Data, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089", false) != null;
}

private static bool Is462Installed()
{
    // API changes in 4.6.2: https://github.com/Microsoft/dotnet/blob/master/releases/net462/dotnet462-api-changes.md
    return Type.GetType("System.Security.Cryptography.AesCng, System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089", false) != null;
}

private static bool Is47Installed()
{
    // API changes in 4.7: https://github.com/Microsoft/dotnet/blob/master/releases/net47/dotnet47-api-changes.md
    return Type.GetType("System.Web.Caching.CacheInsertOptions, System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", false) != null;
}

Environment.Version()为另一个问题给出正确答案。.NET 2.0、3和3.5使用相同版本的CLR。我想您可以检查GAC中每个后续版本中添加的库。

过去很容易，但是Microsoft决定进行重大更改：在4.5版之前，.NET的每个版本都位于其自己的目录下C:\Windows\Microsoft.NET\Framework（子目录v1.0.3705, v1.1.4322, v2.0.50727, v3.0, v3.5和v4.0.30319）。

从4.5版开始，此版本已更改：.NET的每个版本（即4.5.x，4.6.x，4.7.x，4.8.x等）都安装在同一子目录中v4.0.30319-因此您将无法通过查看来检查已安装的.NET版本Microsoft.NET\Framework。

为了检查.NET版本，Microsoft根据要检查的.NET版本提供了两个不同的示例脚本，但是我不喜欢为此使用两个不同的C＃脚本。因此，我尝试将它们组合为一个，这是GetDotNetVersion.cs我创建的脚本（并将其更新为4.7.1框架）：

using System;
using Microsoft.Win32;
public class GetDotNetVersion
{
    public static void Main(string[] args)
    {
        Console.WriteLine((args != null && args.Length > 0) 
                          ? "Command line arguments: " + string.Join(",", args) 
                          : "");

        string maxDotNetVersion = GetVersionFromRegistry();
        if (String.Compare(maxDotNetVersion, "4.5") >= 0)
        {
            string v45Plus = GetDotNetVersion.Get45PlusFromRegistry();
            if (v45Plus != "") maxDotNetVersion = v45Plus;
        }
        Console.WriteLine("*** Maximum .NET version number found is: " + maxDotNetVersion + "***");
    }

    private static string Get45PlusFromRegistry()
    {
        String dotNetVersion = "";
        const string subkey = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\";
        using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(subkey))
        {
            if (ndpKey != null && ndpKey.GetValue("Release") != null)
            {
                dotNetVersion = CheckFor45PlusVersion((int)ndpKey.GetValue("Release"));
                Console.WriteLine(".NET Framework Version: " + dotNetVersion);
            }
            else
            {
                Console.WriteLine(".NET Framework Version 4.5 or later is not detected.");
            }
        }
        return dotNetVersion;
    }

    // Checking the version using >= will enable forward compatibility.
    private static string CheckFor45PlusVersion(int releaseKey)
    {
        if (releaseKey >= 528040) return "4.8 or later";
        if (releaseKey >= 461808) return "4.7.2";
        if (releaseKey >= 461308) return "4.7.1";
        if (releaseKey >= 460798) return "4.7";
        if (releaseKey >= 394802) return "4.6.2";
        if (releaseKey >= 394254) return "4.6.1";
        if (releaseKey >= 393295) return "4.6";
        if ((releaseKey >= 379893)) return "4.5.2";
        if ((releaseKey >= 378675)) return "4.5.1";
        if ((releaseKey >= 378389)) return "4.5";

        // This code should never execute. A non-null release key should mean
        // that 4.5 or later is installed.
        return "No 4.5 or later version detected";
    }

    private static string GetVersionFromRegistry()
    {
        String maxDotNetVersion = "";
        // Opens the registry key for the .NET Framework entry.
        using (RegistryKey ndpKey = RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "")
                                        .OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
        {
            // As an alternative, if you know the computers you will query are running .NET Framework 4.5 
            // or later, you can use:
            // using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, 
            // RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
            foreach (string versionKeyName in ndpKey.GetSubKeyNames())
            {
                if (versionKeyName.StartsWith("v"))
                {
                    RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);
                    string name = (string)versionKey.GetValue("Version", "");
                    string sp = versionKey.GetValue("SP", "").ToString();
                    string install = versionKey.GetValue("Install", "").ToString();
                    if (install == "") //no install info, must be later.
                    {
                        Console.WriteLine(versionKeyName + "  " + name);
                        if (String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                    }
                    else
                    {
                        if (sp != "" && install == "1")
                        {
                            Console.WriteLine(versionKeyName + "  " + name + "  SP" + sp);
                            if (String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                        }

                    }
                    if (name != "")
                    {
                        continue;
                    }
                    foreach (string subKeyName in versionKey.GetSubKeyNames())
                    {
                        RegistryKey subKey = versionKey.OpenSubKey(subKeyName);
                        name = (string)subKey.GetValue("Version", "");
                        if (name != "")
                        {
                            sp = subKey.GetValue("SP", "").ToString();
                        }
                        install = subKey.GetValue("Install", "").ToString();
                        if (install == "")
                        {
                            //no install info, must be later.
                            Console.WriteLine(versionKeyName + "  " + name);
                            if (String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                        }
                        else
                        {
                            if (sp != "" && install == "1")
                            {
                                Console.WriteLine("  " + subKeyName + "  " + name + "  SP" + sp);
                                if (String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                            }
                            else if (install == "1")
                            {
                                Console.WriteLine("  " + subKeyName + "  " + name);
                                if (String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                            } // if
                        } // if
                    } // for
                } // if
            } // foreach
        } // using
        return maxDotNetVersion;
    }
    
} // class

在我的机器上，它输出：

v2.0.50727 2.0.50727.4927 SP2
v3.0 3.0.30729.4926 SP2
v3.5 3.5.30729.4926 SP1
v4
客户端4.7.03056
完整4.7.03056
v4.0
客户端4.0.0.0
.NET Framework版本：4.7.2或更高版本
*** *找到的最大.NET版本号是：4.7.2或更高版本****

随着时间的流逝，唯一需要维护的是.NET版本大于4.7.1时的内部版本号-可以通过修改功能轻松完成CheckFor45PlusVersion，您需要知道新版本的发布密钥，然后可以添加它。例如：

if (releaseKey >= 461308) return "4.7.1 or later";

此发行密钥仍然是最新的密钥，并且对于Windows 10的Fall Creators更新有效。如果您仍在运行其他（旧）Windows版本，则根据Microsoft的此文档，还有另一个版本：

在所有其他Windows OS版本461310上安装的.NET Framework 4.7.1

因此，如果您也需要它，则必须添加

if (releaseKey >= 461310) return "4.7.1 or later";

在函数的顶部CheckFor45PlusVersion。同样，它适用于新版本。例如，我最近添加了4.8的支票。您通常可以在Microsoft找到这些内部版本号。

注意：您不需要安装Visual Studio，甚至不需要PowerShell，您都可以csc.exe用来编译和运行上面的脚本，我已经在此处进行了描述。

更新：问题是关于.NET Framework，为完整起见，我想提一下如何查询.NET Core的版本-与上述相比，这很容易：打开命令外壳并键入：

dotnet --info Enter

它将列出.NET Core版本号，Windows版本以及每个相关运行时DLL的版本。样本输出：

.NET Core SDK（反映任何global.json）：
  版本：2.1.300
  提交：adab45bf0c

运行时环境：
  操作系统名称：Windows
  OS版本：10.0.15063
  操作系统平台：Windows
  RID：win10-x64
  基本路径：C：\ Program Files \ dotnet \ sdk \ 2.1.300


主机（可用于支持）：
  版本：2.1.0
  提交：caa7b7e2ba

安装的.NET Core SDK：
  1.1.9 [C：\ Program Files \ dotnet \ sdk]
  2.1.102 [C：\ Program Files \ dotnet \ sdk]
  ...
  2.1.300 [C：\ Program Files \ dotnet \ sdk]

已安装.NET Core运行时：
  Microsoft.AspNetCore.All 2.1.0 [C：\ Program
  Files \ dotnet \ shared \ Microsoft .AspNetCore.All]
  ...
  Microsoft.NETCore.App 2.1.0 [C：\ Program Files \ dotnet \ shared \ Microsoft.NETCore.App]

要安装其他.NET Core运行时或SDK：https :
  //aka.ms/dotnet-download

注意的是

• 如果您只需要版本号而没有所有其他信息，则可以使用
  dotnet --version。

• 在64位Windows PC上，可以与x64版本的.NET Core并排安装x86版本。在这种情况下，您只会获得环境变量中第一个出现的版本。如果您需要保持最新状态并想了解每个版本，则这一点尤其重要。要查询两个版本，请使用：PATH

C：\ Program Files \ dotnet \ dotnet.exe-版本
3.0.100-preview6-012264
C：\ Program Files \ dotnet \ dotnet.exe-版本
3.0.100-preview6-012264

在上面的示例中，两者相同，但是如果您忘记更新两个实例，则可能会得到不同的结果！请注意，这Program Files是针对64位版本的，并且Program Files (x86)是32位版本。

更新：如果您希望将内部版本号保留在列表中，而不是将if语句级联（如Microsoft建议），则可以使用以下代码CheckFor45PlusVersion代替：

private static string CheckFor45PlusVersion(int releaseKey)
{
    var release = new Dictionary<int, string>()
    {
            { 378389, "4.5" },
            { 378675, "4.5.1" }, { 379893, "4.5.2" },
            { 393295, "4.6" },
            { 394254, "4.6.1" }, { 394802, "4.6.2" },
            { 460798, "4.7" },
            { 461308, "4.7.1" }, { 461808, "4.7.2" },
            { 528040, "4.8 or later" }
    };
    int result = -1;
    foreach(var k in release.OrderBy(k=>k.Key))
    {
        if (k.Key <= releaseKey) result = k.Key; else break;
    };
    return (result > 0) ? release[result] : "No 4.5 or later version detected";
}

AFAIK框架中没有内置的方法可以执行此操作。你可以检查此职位上通过读取注册表值来确定的框架版本的建议。

此类允许您的应用程序抛出优美的通知消息，而不是在找不到正确的.NET版本时崩溃并刻录。您需要做的就是在您的主代码中执行以下操作：

[STAThread]
static void Main(string[] args)
{
    if (!DotNetUtils.IsCompatible())
        return;
   . . .
}

默认情况下，该类为4.5.2，但您可以根据自己的喜好对该类进行调整（可以使用Console随意替换MessageBox）：

更新为4.8：

public class DotNetUtils
{
    public enum DotNetRelease
    {
        NOTFOUND,
        NET45,
        NET451,
        NET452,
        NET46,
        NET461,
        NET462,
        NET47,
        NET471,
        NET472,
        NET48,
    }

    public static bool IsCompatible(DotNetRelease req = DotNetRelease.NET452)
    {
        DotNetRelease r = GetRelease();
        if (r < req)
        {
            MessageBox.Show(String.Format("This this application requires {0} or greater.", req.ToString()));
            return false;
        }
        return true;
    }

    public static DotNetRelease GetRelease(int release = default(int))
    {
        int r = release != default(int) ? release : GetVersion();
        if (r >= 528040) return DotNetRelease.NET48;
        if (r >= 461808) return DotNetRelease.NET472;
        if (r >= 461308) return DotNetRelease.NET471;
        if (r >= 460798) return DotNetRelease.NET47;
        if (r >= 394802) return DotNetRelease.NET462;
        if (r >= 394254) return DotNetRelease.NET461;
        if (r >= 393295) return DotNetRelease.NET46;
        if (r >= 379893) return DotNetRelease.NET452;
        if (r >= 378675) return DotNetRelease.NET451;
        if (r >= 378389) return DotNetRelease.NET45;
        return DotNetRelease.NOTFOUND;
    }

    public static int GetVersion()
    {
        int release = 0;
        using (RegistryKey key = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32)
                                            .OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\"))
        {
            release = Convert.ToInt32(key.GetValue("Release"));
        }
        return release;
    }
}

他们以后添加新版本时可以轻松扩展。在4.5之前我没有打扰任何事情，但是您明白了。

public class DA
{
    public static class VersionNetFramework
    {
        public static string GetVersion()
        {
            return Environment.Version.ToString();
        }
        public static string GetVersionDicription()
        {
            int Major = Environment.Version.Major;
            int Minor = Environment.Version.Minor;
            int Build = Environment.Version.Build;
            int Revision = Environment.Version.Revision;

            //http://dzaebel.net/NetVersionen.htm
            //http://stackoverflow.com/questions/12971881/how-to-reliably-detect-the-actual-net-4-5-version-installed

            //4.0.30319.42000 = .NET 4.6 on Windows 8.1 64 - bit
            if ((Major >=4) && (Minor >=0) && (Build >= 30319) && (Revision >= 42000))
                return @".NET 4.6 on Windows 8.1 64 - bit or later";
            //4.0.30319.34209 = .NET 4.5.2 on Windows 8.1 64 - bit
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 34209))
                return @".NET 4.5.2 on Windows 8.1 64 - bit or later";
            //4.0.30319.34209 = .NET 4.5.2 on Windows 7 SP1 64 - bit
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 34209))
                return @".NET 4.5.2 on Windows 7 SP1 64 - bit or later";
            //4.0.30319.34014 = .NET 4.5.1 on Windows 8.1 64 - bit
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 34014))
                return @".NET 4.5.1 on Windows 8.1 64 - bit or later";
            //4.0.30319.18444 = .NET 4.5.1 on Windows 7 SP1 64 - bit(with MS14 - 009 security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 18444))
                return @".NET 4.5.1 on Windows 7 SP1 64 - bit(with MS14 - 009 security update) or later";
            //4.0.30319.18408 = .NET 4.5.1 on Windows 7 SP1 64 - bit
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 18408))
                return @".NET 4.5.1 on Windows 7 SP1 64 - bit or later";
            //4.0.30319.18063 = .NET 4.5 on Windows 7 SP1 64 - bit(with MS14 - 009 security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 18063))
                return @".NET 4.5 on Windows 7 SP1 64 - bit(with MS14 - 009 security update) or later";
            //4.0.30319.18052 = .NET 4.5 on Windows 7 SP1 64 - bit
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 18052))
                return @".NET 4.5 on Windows 7 SP1 64 - bit or later";
            //4.0.30319.18010 = .NET 4.5 on Windows 8
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 18010))
                return @".NET 4.5 on Windows 8 or later";
            //4.0.30319.17929 = .NET 4.5 RTM
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 17929))
                return @".NET 4.5 RTM or later";
            //4.0.30319.17626 = .NET 4.5 RC
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 17626))
                return @".NET 4.5 RC or later";
            //4.0.30319.17020.NET 4.5 Preview, September 2011
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 17020))
                return @".NET 4.5 Preview, September 2011 or later";
            //4.0.30319.2034 = .NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS14 - 009 LDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 2034))
                return @".NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS14 - 009 LDR security update) or later";
            //4.0.30319.1026 = .NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS14 - 057 GDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 1026))
                return @".NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS14 - 057 GDR security update) or later";
            //4.0.30319.1022 = .NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS14 - 009 GDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 1022))
                return @".NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS14 - 009 GDR security update) or later";
            //4.0.30319.1008 = .NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS13 - 052 GDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 1008))
                return @".NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS13 - 052 GDR security update) or later";
            //4.0.30319.544 = .NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS12 - 035 LDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 544))
                return @".NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS12 - 035 LDR security update) or later";
            //4.0.30319.447   yes built by: RTMLDR, .NET 4.0 Platform Update 1, April 2011
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 447))
                return @"built by: RTMLDR, .NET 4.0 Platform Update 1, April 2011 or later";
            //4.0.30319.431   yes built by: RTMLDR, .NET 4.0 GDR Update, March 2011 / with VS 2010 SP1 / or.NET 4.0 Update
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 431))
                return @"built by: RTMLDR, .NET 4.0 GDR Update, March 2011 / with VS 2010 SP1 / or.NET 4.0 Update or later";
            //4.0.30319.296 = .NET 4.0 on Windows XP SP3, 7(with MS12 - 074 GDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 296))
                return @".NET 4.0 on Windows XP SP3, 7(with MS12 - 074 GDR security update) or later";
            //4.0.30319.276 = .NET 4.0 on Windows XP SP3 (4.0.3 Runtime update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 276))
                return @".NET 4.0 on Windows XP SP3 (4.0.3 Runtime update) or later";
            //4.0.30319.269 = .NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS12 - 035 GDR security update)
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 269))
                return @".NET 4.0 on Windows XP SP3, 7, 7 SP1(with MS12 - 035 GDR security update) or later";
            //4.0.30319.1 yes built by: RTMRel, .NET 4.0 RTM Release, April 2010
            if ((Major >= 4) && (Minor >= 0) && (Build >= 30319) && (Revision >= 1))
                return @"built by: RTMRel, .NET 4.0 RTM Release, April 2010 or later";

            //4.0.30128.1     built by: RC1Rel, .NET 4.0 Release Candidate, Feb 2010
            if ((Major >=4) && (Minor >=0) && (Build >= 30128) && (Revision >= 1))
                return @"built by: RC1Rel, .NET 4.0 Release Candidate, Feb 2010 or later";
            //4.0.21006.1     built by: B2Rel, .NET 4.0 Beta2, Oct 2009
            if ((Major >=4) && (Minor >=0) && (Build >= 21006) && (Revision >=1))
                return @"built by: B2Rel, .NET 4.0 Beta2, Oct 2009 or later";
            //4.0.20506.1     built by: Beta1, .NET 4.0 Beta1, May 2009
            if ((Major >=4) && (Minor >=0) && (Build >= 20506) && (Revision >=1))
                return @"built by: Beta1, .NET 4.0 Beta1, May 2009 or later";
            //4.0.11001.1     built by: CTP2 VPC, .NET 4.0 CTP, October 2008
            if ((Major >=4) && (Minor >=0) && (Build >= 11001) && (Revision >=1))
                return @"built by: CTP2 VPC, .NET 4.0 CTP, October 2008 or later";

            //3.5.30729.5420  yes built by: Win7SP1, .NET 3.5.1 Sicherheits - Update, 12 April 2011
            if ((Major >=3) && (Minor >=5) && (Build >= 30729) && (Revision >= 5420))
                return @"built by: Win7SP1, .NET 3.5.1 Sicherheits - Update, 12 April 2011 or later";
            //3.5.30729.5004  yes built by: NetFXw7 / Windows 7..Rel., Jan 2010 / +Data functions KB976127 .NET 3.5 SP1
            if ((Major >=3) && (Minor >=5) && (Build >= 30729) && (Revision >= 5004))
                return @"built by: NetFXw7 / Windows 7..Rel., Jan 2010 / +Data functions KB976127 .NET 3.5 SP1 or later";
            //3.5.30729.4466  yes built by: NetFXw7 / Windows XP..Rel. , Jan 2010 / +Data functions KB976127 .NET 3.5 SP1
            if ((Major >=3) && (Minor >=5) && (Build >= 30729) && (Revision >= 4466))
                return @"built by: NetFXw7 / Windows XP..Rel. , Jan 2010 / +Data functions KB976127 .NET 3.5 SP1 or later";
            //3.5.30729.4926  yes built by: NetFXw7 / Windows 7 Release, Oct 2009 / .NET 3.5 SP1 + Hotfixes
            if ((Major >=3) && (Minor >=5) && (Build >= 30729) && (Revision >= 4926))
                return @"built by: NetFXw7 / Windows 7 Release, Oct 2009 / .NET 3.5 SP1 + Hotfixes or later";
            //3.5.30729.4918      built by: NetFXw7 / Windows 7 Release Candidate, June 2009
            if ((Major >=3) && (Minor >=5) && (Build >= 30729) && (Revision >= 4918))
                return @"built by: NetFXw7 / Windows 7 Release Candidate, June 2009 or later";
            //3.5.30729.196   yes built by: QFE, .NET 3.5 Family Update Vista / W2008, Dec 2008
            if ((Major >= 3) && (Minor >= 5) && (Build >= 30729) && (Revision >=196))
                return @"built by: QFE, .NET 3.5 Family Update Vista / W2008, Dec 2008 or later";
            //3.5.30729.1 yes built by: SP, .NET 3.5 SP1, Aug 2008
            if ((Major >= 3) && (Minor >= 5) && (Build >= 30729) && (Revision >=1))
                return @"built by: SP, .NET 3.5 SP1, Aug 2008 or later";

            //3.5.30428.1         built by: SP1Beta1, .NET 3.5 SP1 BETA1, May 2008
            if ((Major >=3) && (Minor >=5) && (Build >= 30428) && (Revision >=1))
                return @"built by: SP1Beta1, .NET 3.5 SP1 BETA1, May 2008 or later";
            //3.5.21022.8 yes built by: RTM, Jan 2008
            if ((Major >=3) && (Minor >=5) && (Build >= 21022) && (Revision >= 8))
                return @"built by: RTM, Jan 2008 or later";
            //3.5.20706.1     built by: Beta2, Orcas Beta2, Oct 2007
            if ((Major >=3) && (Minor >=5) && (Build >= 20706) && (Revision >= 1))
                return @"built by: Beta2, Orcas Beta2, Oct 2007 or later";
            //3.5.20526.0     built by: MCritCTP, Orcas Beta1, Mar 2007
            if ((Major >=3) && (Minor >=5) && (Build >= 20526) && (Revision >=0))
                return @"built by: MCritCTP, Orcas Beta1, Mar 2007 or later";

            //3.0.6920.1500   yes built by: QFE, Family Update Vista / W2008, Dez 2008, KB958483
            if ((Major >=3) && (Minor >=0) && (Build >= 6920) && (Revision >= 1500))
                return @"built by: QFE, Family Update Vista / W2008, Dez 2008, KB958483 or later";
            //3.0.4506.4926   yes(NetFXw7.030729 - 4900) / Windows 7 Release, Oct 2009
            if ((Major >=3) && (Minor >=0) && (Build >= 4506) && (Revision >= 4926))
                return @"(NetFXw7.030729 - 4900) / Windows 7 Release, Oct 2009 or later";
            //3.0.4506.4918(NetFXw7.030729 - 4900) / Windows 7 Release Candidate, June 2009
            if ((Major >=3) && (Minor >=5) && (Build >= 4506) && (Revision >= 4918))
                return @"(NetFXw7.030729 - 4900) / Windows 7 Release Candidate, June 2009 or later";
            //3.0.4506.2152       3.0.4506.2152(SP.030729 - 0100) / .NET 4.0 Beta1 / May 2009
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 2152))
                return @"3.0.4506.2152(SP.030729 - 0100) / .NET 4.0 Beta1 / May 2009 or later";
            //3.0.4506.2123   yes(NetFX.030618 - 0000).NET 3.0 SP2, Aug 2008
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 2123))
                return @"s(NetFX.030618 - 0000).NET 3.0 SP2, Aug 2008 or later";
            //3.0.4506.2062(SP1Beta1.030428 - 0100), .NET 3.0 SP1 BETA1, May 2008
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 2062))
                return @"(SP1Beta1.030428 - 0100), .NET 3.0 SP1 BETA1, May 2008 or later";
            //3.0.4506.590(winfxredb2.004506 - 0590), Orcas Beta2, Oct 2007
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 590))
                return @"(winfxredb2.004506 - 0590), Orcas Beta2, Oct 2007 or later";
            //3.0.4506.577(winfxred.004506 - 0577), Orcas Beta1, Mar 2007
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 577))
                return @"(winfxred.004506 - 0577), Orcas Beta1, Mar 2007 or later";
            //3.0.4506.30 yes Release (.NET Framework 3.0) Nov 2006
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 30))
                return @"Release (.NET Framework 3.0) Nov 2006 or later";
            //3.0.4506.25 yes(WAPRTM.004506 - 0026) Vista Ultimate, Jan 2007
            if ((Major >= 3) && (Minor >= 5) && (Build >= 4506) && (Revision >= 25))
                return @"(WAPRTM.004506 - 0026) Vista Ultimate, Jan 2007 or later";

            //2.0.50727.4927  yes(NetFXspW7.050727 - 4900) / Windows 7 Release, Oct 2009
            if ((Major >=2) && (Minor >=0) && (Build >= 50727) && (Revision >= 4927))
                return @"(NetFXspW7.050727 - 4900) / Windows 7 Release, Oct 2009 or later";
            //2.0.50727.4918(NetFXspW7.050727 - 4900) / Windows 7 Release Candidate, June 2009
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 4918))
                return @"(NetFXspW7.050727 - 4900) / Windows 7 Release Candidate, June 2009 or later";
            //2.0.50727.4200  yes(NetFxQFE.050727 - 4200).NET 2.0 SP2, KB974470, Securityupdate, Oct 2009
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 4200))
                return @"(NetFxQFE.050727 - 4200).NET 2.0 SP2, KB974470, Securityupdate, Oct 2009 or later";
            //2.0.50727.3603(GDR.050727 - 3600).NET 4.0 Beta 2, Oct 2009
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 3603))
                return @"(GDR.050727 - 3600).NET 4.0 Beta 2, Oct 2009 or later";
            //2.0.50727.3082  yes(QFE.050727 - 3000), .NET 3.5 Family Update XP / W2003, Dez 2008, KB958481
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 3082))
                return @"(QFE.050727 - 3000), .NET 3.5 Family Update XP / W2003, Dez 2008, KB958481 or later";
            //2.0.50727.3074  yes(QFE.050727 - 3000), .NET 3.5 Family Update Vista / W2008, Dez 2008, KB958481
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 3074))
                return @"(QFE.050727 - 3000), .NET 3.5 Family Update Vista / W2008, Dez 2008, KB958481 or later";
            //2.0.50727.3053  yes(netfxsp.050727 - 3000), .NET 2.0 SP2, Aug 2008
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 3053))
                return @"yes(netfxsp.050727 - 3000), .NET 2.0 SP2, Aug 2008 or later";
            //2.0.50727.3031(netfxsp.050727 - 3000), .NET 2.0 SP2 Beta 1, May 2008
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 3031))
                return @"(netfxsp.050727 - 3000), .NET 2.0 SP2 Beta 1, May 2008 or later";
            //2.0.50727.1434  yes(REDBITS.050727 - 1400), Windows Server 2008 and Windows Vista SP1, Dez 2007
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 1434))
                return @"(REDBITS.050727 - 1400), Windows Server 2008 and Windows Vista SP1, Dez 2007 or later";
            //2.0.50727.1433  yes(REDBITS.050727 - 1400), .NET 2.0 SP1 Release, Nov 2007, http://www.microsoft.com/downloads/details.aspx?FamilyID=79bc3b77-e02c-4ad3-aacf-a7633f706ba5
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 1433))
                return @"(REDBITS.050727 - 1400), .NET 2.0 SP1 Release, Nov 2007 or later";
            //2.0.50727.1378(REDBITSB2.050727 - 1300), Orcas Beta2, Oct 2007
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 1378))
                return @"(REDBITSB2.050727 - 1300), Orcas Beta2, Oct 2007 or later";
            //2.0.50727.1366(REDBITS.050727 - 1300), Orcas Beta1, Mar 2007
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 1366))
                return @"(REDBITS.050727 - 1300), Orcas Beta1, Mar 2007 or later";
            //2.0.50727.867   yes(VS Express Edition 2005 SP1), Apr 2007, http://www.microsoft.com/downloads/details.aspx?FamilyId=7B0B0339-613A-46E6-AB4D-080D4D4A8C4E
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 867))
                return @"(VS Express Edition 2005 SP1), Apr 2007 or later";
            //2.0.50727.832(Fix x86 VC++2005), Apr 2007, http://support.microsoft.com/kb/934586/en-us
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 832))
                return @"(Fix x86 VC++2005), Apr 2007 or later";
            //2.0.50727.762   yes(VS TeamSuite SP1), http://www.microsoft.com/downloads/details.aspx?FamilyId=BB4A75AB-E2D4-4C96-B39D-37BAF6B5B1DC
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 762))
                return @"(VS TeamSuite SP1) or later";
            //2.0.50727.312   yes(rtmLHS.050727 - 3100) Vista Ultimate, Jan 2007
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 312))
                return @"(rtmLHS.050727 - 3100) Vista Ultimate, Jan 2007 or later";
            //2.0.50727.42    yes Release (.NET Framework 2.0) Oct 2005
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 42))
                return @"Release (.NET Framework 2.0) Oct 2005 or later";
            //2.0.50727.26        Version 2.0(Visual Studio Team System 2005 Release Candidate) Oct 2005
            if ((Major >= 2) && (Minor >= 0) && (Build >= 50727) && (Revision >= 26))
                return @"Version 2.0(Visual Studio Team System 2005 Release Candidate) Oct 2005 or later";

            //2.0.50712       Version 2.0(Visual Studio Team System 2005(Drop3) CTP) July 2005
            if ((Major >=2) && (Minor >=0) && (Build >= 50712))
                return @"Version 2.0(Visual Studio Team System 2005(Drop3) CTP) July 2005 or later";
            //2.0.50215       Version 2.0(WinFX SDK for Indigo / Avalon 2005 CTP) July 2005
            if ((Major >=2) && (Minor >=0) && (Build >= 50215))
                return @"Version 2.0(WinFX SDK for Indigo / Avalon 2005 CTP) July 2005 or later";
            //2.0.50601.0     Version 2.0(Visual Studio.NET 2005 CTP) June 2005
            if ((Major >=2) && (Minor >=0) && (Build >= 50601) && (Revision >=0))
                return @"Version 2.0(Visual Studio.NET 2005 CTP) June 2005 or later";
            //2.0.50215.44        Version 2.0(Visual Studio.NET 2005 Beta 2, Visual Studio Express Beta 2) Apr 2005
            if ((Major >=2) && (Minor >=0) && (Build >= 50215) && (Revision >= 44))
                return @"Version 2.0(Visual Studio.NET 2005 Beta 2, Visual Studio Express Beta 2) Apr 2005 or later";
            //2.0.50110.28        Version 2.0(Visual Studio.NET 2005 CTP, Professional Edition) Feb 2005
            if ((Major >=2) && (Minor >=0) && (Build >= 50110) && (Revision >=28))
                return @"Version 2.0(Visual Studio.NET 2005 CTP, Professional Edition) Feb 2005 or later";
            //2.0.41115.19        Version 2.0(Visual Studio.NET 2005 Beta 1, Team System Refresh) Dec 2004
            if ((Major >=2 ) && (Minor >=0 ) && (Build >= 41115) && (Revision >= 19))
                return @"Version 2.0(Visual Studio.NET 2005 Beta 1, Team System Refresh) Dec 2004 or later";
            //2.0.40903.0         Version 2.0(Whidbey CTP, Visual Studio Express) Oct 2004
            if ((Major >=2) && (Minor >=0) && (Build >= 40903) && (Revision >=0))
                return @"Version 2.0(Whidbey CTP, Visual Studio Express) Oct 2004 or later";
            //2.0.40607.85        Version 2.0(Visual Studio.NET 2005 Beta 1, Team System Refresh) Aug 2004 *
            if ((Major >=2) && (Minor >=0) && (Build >= 40607) && (Revision >= 85))
                return @"Version 2.0(Visual Studio.NET 2005 Beta 1, Team System Refresh) Aug 2004 * or later";
            //2.0.40607.42        Version 2.0(SQL Server Yukon Beta 2) July 2004
            if ((Major >=2) && (Minor >=0) && (Build >= 40607) && (Revision >= 42))
                return @"Version 2.0(SQL Server Yukon Beta 2) July 2004 or later";
            //2.0.40607.16        Version 2.0(Visual Studio.NET 2005 Beta 1, TechEd Europe 2004) June 2004
            if ((Major >=2) && (Minor >=0) && (Build >= 40607) && (Revision >= 16))
                return @"Version 2.0(Visual Studio.NET 2005 Beta 1, TechEd Europe 2004) June 2004 or later";
            //2.0.40301.9         Version 2.0(Whidbey CTP, WinHEC 2004) March 2004 *
            if ((Major >=0) && (Minor >=0) && (Build >= 40301) && (Revision >=9))
                return @"Version 2.0(Whidbey CTP, WinHEC 2004) March 2004 * or later";

            //1.2.30703.27        Version 1.2(Whidbey Alpha, PDC 2004) Nov 2003 *
            if ((Major >=1) && (Minor >=2) && (Build >= 30703) && (Revision >= 27))
                return @"Version 1.2(Whidbey Alpha, PDC 2004) Nov 2003 * or later";
            //1.2.21213.1     Version 1.2(Whidbey pre - Alpha build) *
            if ((Major >=1) && (Minor >=2) && (Build >= 21213) && (Revision >=1))
                return @"Version 1.2(Whidbey pre - Alpha build) * or later";

            //1.1.4322.2443   yes Version 1.1 Servicepack 1, KB953297, Oct 2009
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >=2443))
                return @"Version 1.1 Servicepack 1, KB953297, Oct 2009 or later";
            //1.1.4322.2407   yes Version 1.1 RTM
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >= 2407))
                return @"Version 1.1 RTM or later";
            //1.1.4322.2407       Version 1.1 Orcas Beta2, Oct 2007
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >= 2407))
                return @"Version 1.1 Orcas Beta2, Oct 2007 or later";
            //1.1.4322.2379       Version 1.1 Orcas Beta1, Mar 2007
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >= 2379))
                return @"Version 1.1 Orcas Beta1, Mar 2007 or later";
            //1.1.4322.2032   yes Version 1.1 SP1 Aug 2004
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >= 2032))
                return @"Version 1.1 SP1 Aug 2004 or later";
            //1.1.4322.573    yes Version 1.1 RTM(Visual Studio.NET 2003 / Windows Server 2003) Feb 2003 *
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >= 573))
                return @"Version 1.1 RTM(Visual Studio.NET 2003 / Windows Server 2003) Feb 2003 * or later";
            //1.1.4322.510        Version 1.1 Final Beta Oct 2002 *
            if ((Major >=1) && (Minor >=1) && (Build >= 4322) && (Revision >= 510))
                return @"Version 1.1 Final Beta Oct 2002 * or later";

            //1.0.3705.6018   yes Version 1.0 SP3 Aug 2004
            if ((Major >=1) && (Minor >=0) && (Build >= 3705) && (Revision >= 6018))
                return @"Version 1.0 SP3 Aug 2004 or later";
            //1.0.3705.288    yes Version 1.0 SP2 Aug 2002 *
            if ((Major >=1) && (Minor >=0) && (Build >= 3705) && (Revision >= 288))
                return @"Version 1.0 SP2 Aug 2002 * or later";
            //1.0.3705.209    yes Version 1.0 SP1 Mar 2002 *
            if ((Major >=1) && (Minor >=0) && (Build >= 3705) && (Revision >=209))
                return @"Version 1.0 SP1 Mar 2002 * or later";
            //1.0.3705.0  yes Version 1.0 RTM(Visual Studio.NET 2002) Feb 2002 *
            if ((Major >=1) && (Minor >=0) && (Build >= 3705) && (Revision >=0))
                return @"Version 1.0 RTM(Visual Studio.NET 2002) Feb 2002 * or later";
            //1.0.3512.0      Version 1.0 Pre - release RC3(Visual Studio.NET 2002 RC3)
            if ((Major >=1) && (Minor >=0) && (Build >= 3512) && (Revision >=0))
                return @"Version 1.0 Pre - release RC3(Visual Studio.NET 2002 RC3) or later";
            //1.0.2914.16     Version 1.0 Public Beta 2 Jun 2001 *
            if ((Major >=1) && (Minor >=0) && (Build >= 2914) && (Revision >= 16))
                return @"Version 1.0 Public Beta 2 Jun 2001 * or later";
            //1.0.2204.21         Version 1.0 Public Beta 1 Nov 2000 *
            if ((Major >=1) && (Minor >=0) && (Build >= 2204) && (Revision >=21))
                return @"Version 1.0 Public Beta 1 Nov 2000 * or later";

            return @"Unknown .NET version";
        }
    }
}

我遇到了一种情况，可能是从.NET 4.0或更高版本的程序集中调用.NET 4.0类库。

只有从4.5+程序集执行时，特定的方法调用才起作用。

为了确定是否应该调用该方法，我需要确定当前的执行框架版本，这是一个很好的解决方案

var frameworkName = new System.Runtime.Versioning.FrameworkName(
    AppDomain.CurrentDomain.SetupInformation.TargetFrameworkName
);

if (frameworkName.Version >= new Version(4, 5)) 
{
    // run code
}

感谢您的这篇帖子，这是非常有用的。我必须稍作调整，以检查Framework 2.0，因为无法将注册表项直接转换为双精度。这是代码：

string[] version_names = rk.GetSubKeyNames();
//version names start with 'v', eg, 'v3.5'
//we also need to take care of strings like v2.0.50727...
string sCurrent = version_names[version_names.Length - 1].Remove(0, 1);
if (sCurrent.LastIndexOf(".") > 1)
{
    string[] sSplit = sCurrent.Split('.');
    sCurrent = sSplit[0] + "." + sSplit[1] + sSplit[2];
}
double dCurrent = Convert.ToDouble(sCurrent, System.Globalization.CultureInfo.InvariantCulture);
double dExpected = Convert.ToDouble(sExpectedVersion);
if (dCurrent >= dExpected)

public class DA {
  public static class VersionNetFramework {
    public static string Get45or451FromRegistry()
    {//https://msdn.microsoft.com/en-us/library/hh925568(v=vs.110).aspx
        using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\"))
        {
            int releaseKey = Convert.ToInt32(ndpKey.GetValue("Release"));
            if (true)
            {
                return (@"Version: " + CheckFor45DotVersion(releaseKey));
            }
        }
    }
    // Checking the version using >= will enable forward compatibility, 
    // however you should always compile your code on newer versions of
    // the framework to ensure your app works the same.
    private static string CheckFor45DotVersion(int releaseKey)
    {//https://msdn.microsoft.com/en-us/library/hh925568(v=vs.110).aspx
        if (releaseKey >= 394271)
            return "4.6.1 installed on all other Windows OS versions or later";
        if (releaseKey >= 394254)
            return "4.6.1 installed on Windows 10 or later";
        if (releaseKey >= 393297)
            return "4.6 installed on all other Windows OS versions or later";
        if (releaseKey >= 393295)
            return "4.6 installed with Windows 10 or later";
        if (releaseKey >= 379893)
            return "4.5.2 or later";
        if (releaseKey >= 378758)
            return "4.5.1 installed on Windows 8, Windows 7 SP1, or Windows Vista SP2 or later";
        if (releaseKey >= 378675)
            return "4.5.1 installed with Windows 8.1 or later";
        if (releaseKey >= 378389)
            return "4.5 or later";

        return "No 4.5 or later version detected";
    }
    public static string GetVersionFromRegistry()
    {//https://msdn.microsoft.com/en-us/library/hh925568(v=vs.110).aspx
        string res = @"";
        // Opens the registry key for the .NET Framework entry.
        using (RegistryKey ndpKey =
            RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "").
            OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
        {
            // As an alternative, if you know the computers you will query are running .NET Framework 4.5 
            // or later, you can use:
            // using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, 
            // RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
            foreach (string versionKeyName in ndpKey.GetSubKeyNames())
            {
                if (versionKeyName.StartsWith("v"))
                {

                    RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);
                    string name = (string)versionKey.GetValue("Version", "");
                    string sp = versionKey.GetValue("SP", "").ToString();
                    string install = versionKey.GetValue("Install", "").ToString();
                    if (install == "") //no install info, must be later.
                        res += (versionKeyName + "  " + name) + Environment.NewLine;
                    else
                    {
                        if (sp != "" && install == "1")
                        {
                            res += (versionKeyName + "  " + name + "  SP" + sp) + Environment.NewLine;
                        }

                    }
                    if (name != "")
                    {
                        continue;
                    }
                    foreach (string subKeyName in versionKey.GetSubKeyNames())
                    {
                        RegistryKey subKey = versionKey.OpenSubKey(subKeyName);
                        name = (string)subKey.GetValue("Version", "");
                        if (name != "")
                            sp = subKey.GetValue("SP", "").ToString();
                        install = subKey.GetValue("Install", "").ToString();
                        if (install == "") //no install info, must be later.
                            res += (versionKeyName + "  " + name) + Environment.NewLine;
                        else
                        {
                            if (sp != "" && install == "1")
                            {
                                res += ("  " + subKeyName + "  " + name + "  SP" + sp) + Environment.NewLine;
                            }
                            else if (install == "1")
                            {
                                res += ("  " + subKeyName + "  " + name) + Environment.NewLine;
                            }
                        }
                    }
                }
            }
        }
        return res;
    }
    public static string GetUpdateHistory()
    {//https://msdn.microsoft.com/en-us/library/hh925567(v=vs.110).aspx
        string res=@"";
        using (RegistryKey baseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\Updates"))
        {
            foreach (string baseKeyName in baseKey.GetSubKeyNames())
            {
                if (baseKeyName.Contains(".NET Framework") || baseKeyName.StartsWith("KB") || baseKeyName.Contains(".NETFramework"))
                {

                    using (RegistryKey updateKey = baseKey.OpenSubKey(baseKeyName))
                    {
                        string name = (string)updateKey.GetValue("PackageName", "");
                        res += baseKeyName + "  " + name + Environment.NewLine;
                        foreach (string kbKeyName in updateKey.GetSubKeyNames())
                        {
                            using (RegistryKey kbKey = updateKey.OpenSubKey(kbKeyName))
                            {
                                name = (string)kbKey.GetValue("PackageName", "");
                                res += ("  " + kbKeyName + "  " + name) + Environment.NewLine;

                                if (kbKey.SubKeyCount > 0)
                                {
                                    foreach (string sbKeyName in kbKey.GetSubKeyNames())
                                    {
                                        using (RegistryKey sbSubKey = kbKey.OpenSubKey(sbKeyName))
                                        {
                                            name = (string)sbSubKey.GetValue("PackageName", "");
                                            if (name == "")
                                                name = (string)sbSubKey.GetValue("Description", "");
                                            res += ("    " + sbKeyName + "  " + name) + Environment.NewLine;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
        return res;
    }
}

使用类DA.VersionNetFramework

private void Form1_Shown(object sender, EventArgs e)
{
    //
    // Current OS Information
    //
    richTextBox1.Text = @"Current OS Information:";
    richTextBox1.AppendText(Environment.NewLine +
                            "Machine Name: " + Environment.MachineName);
    richTextBox1.AppendText(Environment.NewLine +
                            "Platform: " + Environment.OSVersion.Platform.ToString());
    richTextBox1.AppendText(Environment.NewLine +
                            Environment.OSVersion);
    //
    // .NET Framework Environment Information
    //
    richTextBox1.AppendText(Environment.NewLine + Environment.NewLine +
                                       ".NET Framework Environment Information:");
    richTextBox1.AppendText(Environment.NewLine +
                            "Environment.Version " + Environment.Version);
    richTextBox1.AppendText(Environment.NewLine + 
                            DA.VersionNetFramework.GetVersionDicription());
    //
    // .NET Framework Information From Registry
    //
    richTextBox1.AppendText(Environment.NewLine + Environment.NewLine +
                                       ".NET Framework Information From Registry:");
    richTextBox1.AppendText(Environment.NewLine +
                            DA.VersionNetFramework.GetVersionFromRegistry());
    //
    // .NET Framework 4.5 or later Information From Registry
    //
    richTextBox1.AppendText(Environment.NewLine + 
                                       ".NET Framework 4.5 or later Information From Registry:");
    richTextBox1.AppendText(Environment.NewLine +
                            DA.VersionNetFramework.Get45or451FromRegistry());
    //
    // Update History
    //
    richTextBox1.AppendText(Environment.NewLine + Environment.NewLine +
                            "Update History");
    richTextBox1.AppendText(Environment.NewLine + 
                            DA.VersionNetFramework.GetUpdateHistory());
    //
    // Setting Cursor to first character of textbox
    //
    if (!richTextBox1.Text.Equals(""))
    {
        richTextBox1.SelectionStart = 1;
    }
}

结果：

当前操作系统信息：机器名称：D1平台：Win32NT Microsoft Windows NT 6.2.9200.0

.NET Framework环境信息：Windows 8.1 64位或更高版本上的Environment.Version 4.0.30319.42000 .NET 4.6

来自注册表的.NET Framework信息：v2.0.50727 2.0.50727.4927 SP2 v3.0 3.0.30729.4926 SP2 v3.5 3.5.30729.4926 SP1

v4
客户端4.6.00079完整版4.6.00079 v4.0
客户端4.0.0.0

.NET Framework 4.5或更高版本来自注册表的信息：版本：4.6与Windows 10或更高版本一起安装

更新历史记录Microsoft .NET Framework 4客户端配置文件
KB2468871
KB2468871v2
KB2478063
KB2533523
KB2544514
KB2600211
KB2600217
Microsoft .NET Framework 4扩展
KB2468871
KB2468871v2
KB2478063
KB2533523
KB2544514
KB2600211
KB2600217
Microsoft .NET Framework 4多目标包
KB2504637（KB2504637）更新

我更改了Matt的类，因此可以在任何项目中重用它，而无需在控制台上打印其所有检查并返回安装了正确的最大版本的简单字符串。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Win32;

namespace MyNamespace
{
    public class DotNetVersion
    {
        protected bool printVerification;

        public DotNetVersion(){
            this.printVerification=false;
        }
        public DotNetVersion(bool printVerification){
            this.printVerification=printVerification;
        }


        public string getDotNetVersion(){
            string maxDotNetVersion = getVersionFromRegistry();
            if(String.Compare(maxDotNetVersion, "4.5") >= 0){
                string v45Plus = get45PlusFromRegistry();
                if(!string.IsNullOrWhiteSpace(v45Plus)) maxDotNetVersion = v45Plus;
            }
            log("*** Maximum .NET version number found is: " + maxDotNetVersion + "***");

            return maxDotNetVersion;
        }

        protected string get45PlusFromRegistry(){
            String dotNetVersion = "";
            const string subkey = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\";
            using(RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(subkey)){
                if(ndpKey != null && ndpKey.GetValue("Release") != null){
                    dotNetVersion = checkFor45PlusVersion((int)ndpKey.GetValue("Release"));
                    log(".NET Framework Version: " + dotNetVersion);
                }else{
                    log(".NET Framework Version 4.5 or later is not detected.");
                }
            }
            return dotNetVersion;
        }

        // Checking the version using >= will enable forward compatibility.
        protected string checkFor45PlusVersion(int releaseKey){
            if(releaseKey >= 461308) return "4.7.1 or later";
            if(releaseKey >= 460798) return "4.7";
            if(releaseKey >= 394802) return "4.6.2";
            if(releaseKey >= 394254) return "4.6.1";
            if(releaseKey >= 393295) return "4.6";
            if((releaseKey >= 379893)) return "4.5.2";
            if((releaseKey >= 378675)) return "4.5.1";
            if((releaseKey >= 378389)) return "4.5";

            // This code should never execute. A non-null release key should mean
            // that 4.5 or later is installed.
            log("No 4.5 or later version detected");
            return "";
        }

        protected string getVersionFromRegistry(){
            String maxDotNetVersion = "";
            // Opens the registry key for the .NET Framework entry.
            using(RegistryKey ndpKey = RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "")
                                            .OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\")){
                // As an alternative, if you know the computers you will query are running .NET Framework 4.5 
                // or later, you can use:
                // using(RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, 
                // RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
                string[] subKeyNnames = ndpKey.GetSubKeyNames();
                foreach(string versionKeyName in subKeyNnames){
                    if(versionKeyName.StartsWith("v")){
                        RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);
                        string name =(string)versionKey.GetValue("Version", "");
                        string sp = versionKey.GetValue("SP", "").ToString();
                        string install = versionKey.GetValue("Install", "").ToString();
                        if(string.IsNullOrWhiteSpace(install)){ //no install info, must be later.
                            log(versionKeyName + "  " + name);
                            if(String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                        }else{
                            if(!string.IsNullOrWhiteSpace(sp) && "1".Equals(install)){
                                log(versionKeyName + "  " + name + "  SP" + sp);
                                if(String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                            }

                        }
                        if(!string.IsNullOrWhiteSpace(name)){
                            continue;
                        }

                        string[] subKeyNames = versionKey.GetSubKeyNames();
                        foreach(string subKeyName in subKeyNames){
                            RegistryKey subKey = versionKey.OpenSubKey(subKeyName);
                            name =(string)subKey.GetValue("Version", "");
                            if(!string.IsNullOrWhiteSpace(name)){
                                sp = subKey.GetValue("SP", "").ToString();
                            }
                            install = subKey.GetValue("Install", "").ToString();
                            if(string.IsNullOrWhiteSpace(install)){
                                //no install info, must be later.
                                log(versionKeyName + "  " + name);
                                if(String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                            }else{
                                if(!string.IsNullOrWhiteSpace(sp) && "1".Equals(install)){
                                    log("  " + subKeyName + "  " + name + "  SP" + sp);
                                    if(String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                                }
                                else if("1".Equals(install)){
                                    log("  " + subKeyName + "  " + name);
                                    if(String.Compare(maxDotNetVersion, name) < 0) maxDotNetVersion = name;
                                } // if
                            } // if
                        } // for
                    } // if
                } // foreach
            } // using
            return maxDotNetVersion;
        }

        protected void log(string message){
            if(printVerification) Console.WriteLine(message);
        }

    } // class
}

我试图将所有答案合并为一个整体。

使用：

NetFrameworkUtilities.GetVersion()将在此时返回当前可用的.NET Framework版本；如果不存在，则返回null。

此示例在.NET Framework 3.5+版本中有效。它不需要管理员权限。

我想指出，您可以使用运算符<和>来检查版本，如下所示：

var version = NetFrameworkUtilities.GetVersion();
if (version != null && version < new Version(4, 5))
{
    MessageBox.Show("Your .NET Framework version is less than 4.5");
}

码：

using System;
using System.Linq;
using Microsoft.Win32;

namespace Utilities
{
    public static class NetFrameworkUtilities
    {
        public static Version GetVersion() => GetVersionHigher4() ?? GetVersionLowerOr4();

        private static Version GetVersionLowerOr4()
        {
            using (var key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP"))
            {
                var names = key?.GetSubKeyNames();

                //version names start with 'v', eg, 'v3.5' which needs to be trimmed off before conversion
                var text = names?.LastOrDefault()?.Remove(0, 1);
                if (string.IsNullOrEmpty(text))
                {
                    return null;
                }

                return text.Contains('.')
                    ? new Version(text)
                    : new Version(Convert.ToInt32(text), 0);
            }
        }

        private static Version GetVersionHigher4()
        {
            using (var key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full"))
            {
                var value = key?.GetValue("Release");
                if (value == null)
                {
                    return null;
                }

                // Checking the version using >= will enable forward compatibility,  
                // however you should always compile your code on newer versions of 
                // the framework to ensure your app works the same. 
                var releaseKey = Convert.ToInt32(value);
                if (releaseKey >= 461308) return new Version(4, 7, 1);
                if (releaseKey >= 460798) return new Version(4, 7);
                if (releaseKey >= 394747) return new Version(4, 6, 2);
                if (releaseKey >= 394254) return new Version(4, 6, 1);
                if (releaseKey >= 381029) return new Version(4, 6);
                if (releaseKey >= 379893) return new Version(4, 5, 2);
                if (releaseKey >= 378675) return new Version(4, 5, 1);
                if (releaseKey >= 378389) return new Version(4, 5);

                // This line should never execute. A non-null release key should mean 
                // that 4.5 or later is installed. 
                return new Version(4, 5);
            }
        }
    }
}

使用.NET 4.6.2更新。在与以前的响应相同的注册表中检查“释放值”：

RegistryKey registry_key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full");
if (registry_key == null)
    return false;
var val = registry_key.GetValue("Release", 0);
UInt32 Release = Convert.ToUInt32(val);

if (Release >= 394806) // 4.6.2 installed on all other Windows (different than Windows 10)
                return true;
if (Release >= 394802) // 4.6.2 installed on Windows 10 or later
                return true;

稍大一些，但看起来是Microsoft的最新信息：

    public static class Versions
    {
        static Version 
            _NET;

        static SortedList<String,Version>
            _NETInstalled;

#if NET40
#else
        public static bool VersionTry(String S, out Version V)
        {
            try
            { 
                V=new Version(S); 
                return true;
            }
            catch
            {
                V=null;
                return false;
            }
        }
#endif
        const string _NetFrameWorkKey = "SOFTWARE\\Microsoft\\NET Framework Setup\\NDP";
        static void FillNetInstalled()
        {
            if (_NETInstalled == null)
            {
                _NETInstalled = new SortedList<String, Version>(StringComparer.InvariantCultureIgnoreCase);
                RegistryKey
                    frmks = Registry.LocalMachine.OpenSubKey(_NetFrameWorkKey);
                string[]
                    names = frmks.GetSubKeyNames();
                foreach (string name in names)
                {
                    if (name.StartsWith("v", StringComparison.InvariantCultureIgnoreCase) && name.Length > 1)
                    {
                        string
                            f, vs;
                        Version
                            v;
                        vs = name.Substring(1);
                        if (vs.IndexOf('.') < 0)
                            vs += ".0";
#if NET40
                        if (Version.TryParse(vs, out v))
#else
                        if (VersionTry(vs, out v))
#endif
                        {
                            f = String.Format("{0}.{1}", v.Major, v.Minor);
#if NET40
                            if (Version.TryParse((string)frmks.OpenSubKey(name).GetValue("Version"), out v))
#else
                            if (VersionTry((string)frmks.OpenSubKey(name).GetValue("Version"), out v))
#endif
                            {
                                if (!_NETInstalled.ContainsKey(f) || v.CompareTo(_NETInstalled[f]) > 0)
                                    _NETInstalled[f] = v;
                            }
                            else
                            { // parse variants
                                Version
                                    best = null;
                                if (_NETInstalled.ContainsKey(f))
                                    best = _NETInstalled[f];
                                string[]
                                    varieties = frmks.OpenSubKey(name).GetSubKeyNames();
                                foreach (string variety in varieties)
#if NET40
                                    if (Version.TryParse((string)frmks.OpenSubKey(name + '\\' + variety).GetValue("Version"), out v))
#else
                                    if (VersionTry((string)frmks.OpenSubKey(name + '\\' + variety).GetValue("Version"), out v))
#endif
                                    {
                                        if (best == null || v.CompareTo(best) > 0)
                                        {
                                            _NETInstalled[f] = v;
                                            best = v;
                                        }
                                        vs = f + '.' + variety;
                                        if (!_NETInstalled.ContainsKey(vs) || v.CompareTo(_NETInstalled[vs]) > 0)
                                            _NETInstalled[vs] = v;
                                    }
                            }
                        }
                    }
                }
            }
        } // static void FillNetInstalled()

        public static Version NETInstalled
        {
            get
            {
                FillNetInstalled();
                return _NETInstalled[_NETInstalled.Keys[_NETInstalled.Count-1]];
            }
        } // NETInstalled

        public static Version NET
        {
            get
            {
                FillNetInstalled();
                string
                    clr = String.Format("{0}.{1}", Environment.Version.Major, Environment.Version.Minor);
                Version
                    found = _NETInstalled[_NETInstalled.Keys[_NETInstalled.Count-1]];
                if(_NETInstalled.ContainsKey(clr))
                    return _NETInstalled[clr];

                for (int i = _NETInstalled.Count - 1; i >= 0; i--)
                    if (_NETInstalled.Keys[i].CompareTo(clr) < 0)
                        return found;
                    else
                        found = _NETInstalled[_NETInstalled.Keys[i]];
                return found;
            }
        } // NET
    }

从4.5版开始，Microsoft更改了将.NET Framework指示器存储在注册表中的方式。有关如何检索.NET框架和CLR版本的官方指南，可以在这里找到：https : //msdn.microsoft.com/zh-cn/library/hh925568(v=vs.110).aspx

我在其中包含其代码的修改版本，以解决有关如何确定4.5及更高版本的.NET框架的悬而未决的问题：

using System;
using System.Reflection;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Win32;

namespace stackoverflowtesting
{
    class Program
    {
        static void Main(string[] args)
        {
            Dictionary<int, String> mappings = new Dictionary<int, string>();

            mappings[378389] = "4.5";
            mappings[378675] = "4.5.1 on Windows 8.1";
            mappings[378758] = "4.5.1 on Windows 8, Windows 7 SP1, and Vista";
            mappings[379893] = "4.5.2";
            mappings[393295] = "4.6 on Windows 10";
            mappings[393297] = "4.6 on Windows not 10";

            using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\"))
            {
                int releaseKey = Convert.ToInt32(ndpKey.GetValue("Release"));
                if (true)
                {
                    Console.WriteLine("Version: " + mappings[releaseKey]);
                }
            }
            int a = Console.Read();
        }
    }
}

这是我找到的解决方案：

private static string GetDotNetVersion()
{
  var v4 = (string)Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full", false)?.GetValue("Version");
  if(v4 != null)
    return v4;
  var v35 = (string)Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\v3.5", false)?.GetValue("Version");
  if(v35 != null)
    return v35;
  var v3 = (string)Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\v3.0", false)?.GetValue("Version");
  return v3 ?? "< 3";
}

        public static class DotNetHelper
{
    public static Version InstalledVersion
    {
        get
        {
            string framework = null;

            try
            {
                using (var ndpKey =
            Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\"))
                {
                    if (ndpKey != null)
                    {
                        var releaseKey = ndpKey.GetValue("Release");
                        if (releaseKey != null)
                        {
                            framework = CheckFor45PlusVersion(Convert.ToInt32(releaseKey));
                        }
                        else
                        {
                            string[] versionNames = null;
                            using (var installedVersions =
                                Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP"))
                            {
                                if (installedVersions != null) versionNames = installedVersions.GetSubKeyNames();
                            }


                            try
                            {
                                if (versionNames != null && versionNames.Length > 0)
                                {
                                    framework = versionNames[versionNames.Length - 1].Remove(0, 1);
                                }
                            }
                            catch (FormatException)
                            {

                            }
                        }
                    }
                }
            }
            catch (SecurityException)
            {
            }

            return framework != null ? new Version(framework) : null;
        }
    }

    private static string CheckFor45PlusVersion(int releaseKey)
    {
        if (releaseKey >= 460798)
            return "4.7";
        if (releaseKey >= 394802)
            return "4.6.2";
        if (releaseKey >= 394254)
            return "4.6.1";
        if (releaseKey >= 393295)
            return "4.6";
        if (releaseKey >= 379893)
            return "4.5.2";
        if (releaseKey >= 378675)
            return "4.5.1";
        // This code should never execute. A non-null release key should mean
        // that 4.5 or later is installed.
        return releaseKey >= 378389 ? "4.5" : null;
    }
}

如果您的计算机已连接到Internet，则转至Minimumdotnet，下载并执行.NET Checker可能是最简单的方法。

如果您需要确定版本的实际方法，请在github，esp上查看其源代码。该Constants.cs这将有助于你的.NET 4.5及更高版本，其中修改的部分是relvant之一：

                           { int.MinValue, "4.5" },
                           { 378389, "4.5" },
                           { 378675, "4.5.1" },
                           { 378758, "4.5.1" },
                           { 379893, "4.5.2" },
                           { 381029, "4.6 Preview" },
                           { 393273, "4.6 RC1" },
                           { 393292, "4.6 RC2" },
                           { 393295, "4.6" },
                           { 393297, "4.6" },
                           { 394254, "4.6.1" },
                           { 394271, "4.6.1" },
                           { 394747, "4.6.2 Preview" },
                           { 394748, "4.6.2 Preview" },
                           { 394757, "4.6.2 Preview" },
                           { 394802, "4.6.2" },
                           { 394806, "4.6.2" },

我发现与该Version班一起工作更容易：

using Microsoft.Win32;
using System.Runtime.InteropServices;

namespace System.Runtime.InteropServices {
  public static class RuntimeInformationEx {

    public static Version? GetDotnetFrameworkVersion() {
      using var key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full");
      if (key is object) {
        if (!Int32.TryParse(key.GetValue("Release", "").ToString(), out var release)) return null;
        return release switch
        {
          378389 => new Version(4, 5, 0),
          378675 => new Version(4, 5, 1),
          378758 => new Version(4, 5, 1),
          379893 => new Version(4, 5, 2),
          393295 => new Version(4, 6, 0),
          393297 => new Version(4, 6, 0),
          394254 => new Version(4, 6, 1),
          394271 => new Version(4, 6, 1),
          394802 => new Version(4, 6, 2),
          394806 => new Version(4, 6, 2),
          460798 => new Version(4, 7, 0),
          460805 => new Version(4, 7, 0),
          461308 => new Version(4, 7, 1),
          461310 => new Version(4, 7, 1),
          461808 => new Version(4, 7, 2),
          461814 => new Version(4, 7, 2),
          528040 => new Version(4, 8, 0),
          528209 => new Version(4, 8, 0),
          528049 => new Version(4, 8, 0),
          _ => null
        };

      } else { // .NET version < 4.5
        using var key1 = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
        if (key1 is null) return null;
        var parts = key1.GetSubKeyNames()[^1].Substring(1).Split('.'); // get lastsub key, remove 'v' prefix, and split
        if (parts.Length == 2) parts = new string[] { parts[0], parts[1], "0" };
        if (parts.Length != 3) return null;
        Func<string, int> Parse = s => Int32.TryParse(s, out var i) ? i : -1;
        try { return new Version(Parse(parts[0]), Parse(parts[1]), Parse(parts[2])); } catch { return null; }
      }
    }

    public static Version? GetDotnetCoreVersion() {
      if (!RuntimeInformation.FrameworkDescription.StartsWith(".NET Core ")) return null;
      var parts = RuntimeInformation.FrameworkDescription.Substring(10).Split('.');
      if (parts.Length == 2) parts = new string[] { parts[0], parts[1], "0" };
      if (parts.Length != 3) return null;
      Func<string, int> Parse = s => Int32.TryParse(s, out var i) ? i : -1;
      try { return new Version(Parse(parts[0]), Parse(parts[1]), Parse(parts[2])); } catch { return null; }
    }
  }
}

（代码为C＃8）

您可以获得有用的字符串，而不必触摸可能已加载或未加载的注册表或参考程序集。mscorlib.dll和其他系统程序集定义了AssemblyFileVersionAttribute，并且根据Visual Studio附带的参考程序集，对于每个.NET版本，它似乎都是唯一的。

string version = (typeof(string).Assembly
    .GetCustomAttributes(typeof(AssemblyFileVersionAttribute), false)
    .FirstOrDefault() as AssemblyFileVersionAttribute)?.Version;

4.5版有点过时，因为在该版本中标记为4.0，但从4.6版开始至少具有次要版本匹配。这样做比与依赖某些安装程序注册表项并必须与一组固定值进行比较似乎更具前瞻性。

我在这里找到了参考程序集：

C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework

我在哪里得到以下版本：

4.0 = 4.0.30319.1
4.5 = 4.0.30319.18020
4.5.1 = 4.0.30319.18402
4.5.2 = 4.0.30319.34211
4.6 = 4.6.81.0
4.6.1 = 4.6.1055.0
4.7.2 = 4.7.3062.0
4.8 = 4.8.3761.0

试试这个：

string GetFrameWorkVersion()
    {
        return System.Runtime.InteropServices.RuntimeEnvironment.GetSystemVersion();
    }