如何在ASP.NET CORE中获取客户端IP地址？

您能否让我知道在使用MVC 6 Request.ServerVariables["REMOTE_ADDR"]无法正常工作时如何在ASP.NET中获取客户端IP地址。

API已更新。不确定何时更改，但是据达米安·爱德华兹（Damien Edwards）所说，您现在可以执行以下操作：

var remoteIpAddress = request.HttpContext.Connection.RemoteIpAddress;

在project.json中将依赖项添加到：

"Microsoft.AspNetCore.HttpOverrides": "1.0.0"

在Startup.cs中的Configure()方法中，添加：

  app.UseForwardedHeaders(new ForwardedHeadersOptions
        {
            ForwardedHeaders = ForwardedHeaders.XForwardedFor |
            ForwardedHeaders.XForwardedProto
        });  

而且当然：

using Microsoft.AspNetCore.HttpOverrides;

然后，我可以使用以下命令获取ip：

Request.HttpContext.Connection.RemoteIpAddress

就我而言，在VS中进行调试时，我总是拥有IpV6本地主机，但是在IIS上部署时，我总是具有远程IP。

一些有用的链接： 如何在ASP.NET CORE中获取客户端IP地址？并且RemoteIpAddress始终为null

该::1也许是因为：

IIS处的连接终止，然后将其转发到v.next Web服务器Kestrel，因此与Web服务器的连接确实来自本地主机。（https://stackoverflow.com/a/35442401/5326387）

可以添加一些后备逻辑来处理负载均衡器的存在。

另外，通过检查，X-Forwarded-For即使没有负载均衡器，报头也可能会被设置（可能是由于附加的Kestrel层？）：

public string GetRequestIP(bool tryUseXForwardHeader = true)
{
    string ip = null;

    // todo support new "Forwarded" header (2014) https://en.wikipedia.org/wiki/X-Forwarded-For

    // X-Forwarded-For (csv list):  Using the First entry in the list seems to work
    // for 99% of cases however it has been suggested that a better (although tedious)
    // approach might be to read each IP from right to left and use the first public IP.
    // http://stackoverflow.com/a/43554000/538763
    //
    if (tryUseXForwardHeader)
        ip = GetHeaderValueAs<string>("X-Forwarded-For").SplitCsv().FirstOrDefault();

    // RemoteIpAddress is always null in DNX RC1 Update1 (bug).
    if (ip.IsNullOrWhitespace() && _httpContextAccessor.HttpContext?.Connection?.RemoteIpAddress != null)
        ip = _httpContextAccessor.HttpContext.Connection.RemoteIpAddress.ToString();

    if (ip.IsNullOrWhitespace())
        ip = GetHeaderValueAs<string>("REMOTE_ADDR");

    // _httpContextAccessor.HttpContext?.Request?.Host this is the local host.

    if (ip.IsNullOrWhitespace())
        throw new Exception("Unable to determine caller's IP.");

    return ip;
}

public T GetHeaderValueAs<T>(string headerName)
{
    StringValues values;

    if (_httpContextAccessor.HttpContext?.Request?.Headers?.TryGetValue(headerName, out values) ?? false)
    {
        string rawValues = values.ToString();   // writes out as Csv when there are multiple.

        if (!rawValues.IsNullOrWhitespace())
            return (T)Convert.ChangeType(values.ToString(), typeof(T));
    }
    return default(T);
}

public static List<string> SplitCsv(this string csvList, bool nullOrWhitespaceInputReturnsNull = false)
{
    if (string.IsNullOrWhiteSpace(csvList))
        return nullOrWhitespaceInputReturnsNull ? null : new List<string>();

    return csvList
        .TrimEnd(',')
        .Split(',')
        .AsEnumerable<string>()
        .Select(s => s.Trim())
        .ToList();
}

public static bool IsNullOrWhitespace(this string s)
{
    return String.IsNullOrWhiteSpace(s);
}

假设_httpContextAccessor是通过DI提供的。

您可以使用IHttpConnectionFeature获取此信息。

var remoteIpAddress = httpContext.GetFeature<IHttpConnectionFeature>()?.RemoteIpAddress;

var remoteIpAddress = HttpContext.Features.Get<IHttpConnectionFeature>()?.RemoteIpAddress;

在ASP.NET 2.1中，在StartUp.cs中添加以下服务：

services.AddHttpContextAccessor();
services.TryAddSingleton<IActionContextAccessor, ActionContextAccessor>();

然后做3步：

1. 在您的MVC控制器中定义一个变量

   private IHttpContextAccessor _accessor;

2. DI进入控制器的构造函数

   public SomeController(IHttpContextAccessor accessor)
   {
       _accessor = accessor;
   }

3. 检索IP地址

   _accessor.HttpContext.Connection.RemoteIpAddress.ToString()

这是完成的方式。

这对我有用（DotNetCore 2.1）

[HttpGet]
public string Get() 
{
    var remoteIpAddress = HttpContext.Connection.RemoteIpAddress;
    return remoteIpAddress.ToString();
}

就我而言，我拥有在DigitalOcean上运行的DotNet Core 2.2 Web App，并使用docker和nginx作为反向代理。使用Startup.cs中的这段代码，我可以获得客户端IP

app.UseForwardedHeaders(new ForwardedHeadersOptions
        {
            ForwardedHeaders = ForwardedHeaders.All,
            RequireHeaderSymmetry = false,
            ForwardLimit = null,
            KnownNetworks = { new IPNetwork(IPAddress.Parse("::ffff:172.17.0.1"), 104) }
        });

:: ffff：172.17.0.1是我在使用之前获得的IP

Request.HttpContext.Connection.RemoteIpAddress.ToString();

首先，在.Net Core 1.0中添加using Microsoft.AspNetCore.Http.Features;到控制器，然后在相关方法内部：

var ip = HttpContext.Features.Get<IHttpConnectionFeature>()?.RemoteIpAddress?.ToString();

我读了其他一些未能编译的答案，因为它使用的是小写的httpContext，导致VS使用Microsoft.AspNetCore.Http（而不是适当的用法）或HttpContext添加（编译器也会误导）。

在.net核心中获取ipaddress和主机名

将此代码放入控制器

跟着这些步骤：

var addlist = Dns.GetHostEntry(Dns.GetHostName());
string GetHostName = addlist.HostName.ToString();
string GetIPV6 = addlist.AddressList[0].ToString();
string GetIPV4 = addlist.AddressList[1].ToString();

我发现，有些人发现您获得的IP地址是::: 1或0.0.0.1

之所以会出现此问题，是因为您尝试从自己的计算机上获取IP，以及C＃试图返回IPv6的困惑。

因此，我实现了@Johna（https://stackoverflow.com/a/41335701/812720）和@David（https://stackoverflow.com/a/8597351/812720）的答案，感谢他们！

并在这里解决：

1. 在您的引用（依赖项/包）中添加Microsoft.AspNetCore.HttpOverrides包

2. 在Startup.cs中添加此行

   public void Configure(IApplicationBuilder app, IHostingEnvironment env)
   {
       // your current code
   
       // start code to add
       // to get ip address
       app.UseForwardedHeaders(new ForwardedHeadersOptions
       {
       ForwardedHeaders = ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto
       });
       // end code to add
   
   }

3. 要获取IPAddress，请在您的任何Controller.cs中使用此代码

   IPAddress remoteIpAddress = Request.HttpContext.Connection.RemoteIpAddress;
   string result = "";
   if (remoteIpAddress != null)
   {
       // If we got an IPV6 address, then we need to ask the network for the IPV4 address 
       // This usually only happens when the browser is on the same machine as the server.
       if (remoteIpAddress.AddressFamily == System.Net.Sockets.AddressFamily.InterNetworkV6)
       {
           remoteIpAddress = System.Net.Dns.GetHostEntry(remoteIpAddress).AddressList
   .First(x => x.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork);
       }
       result = remoteIpAddress.ToString();
   }

现在您可以从remoteIpAddress或result获取IPv4地址

试试这个。

var host = Dns.GetHostEntry(Dns.GetHostName());
        foreach (var ip in host.AddressList)
        {
            if (ip.AddressFamily == AddressFamily.InterNetwork)
            {
                 ipAddress = ip.ToString();
            }
        }

在负载均衡器后面运行.NET core（3.1.4）IIS不能与其他建议的解决方案一起使用。

手动读取X-Forwarded-For标头确实如此。

IPAddress ip;
var headers = Request.Headers.ToList();
if (headers.Exists((kvp) => kvp.Key == "X-Forwarded-For"))
{
    // when running behind a load balancer you can expect this header
    var header = headers.First((kvp) => kvp.Key == "X-Forwarded-For").Value.ToString();
    ip = IPAddress.Parse(header);
}
else
{
    // this will always have a value (running locally in development won't have the header)
    ip = Request.HttpContext.Connection.RemoteIpAddress;
}

我正在使用托管捆绑包运行一个自包含的软件包。

在Ubuntu上的Traefik反向代理后面运行ASP.NET Core 2.1，我需要KnownProxies在安装官方Microsoft.AspNetCore.HttpOverrides软件包后设置其网关IP

        var forwardedOptions = new ForwardedHeadersOptions {
            ForwardedHeaders = ForwardedHeaders.XForwardedFor,
        };
        forwardedOptions.KnownProxies.Add(IPAddress.Parse("192.168.3.1"));
        app.UseForwardedHeaders(forwardedOptions);

根据文档，如果反向代理未在本地主机上运行，​​则这是必需的。该docker-compose.ymlTraefik已经分配了一个静态IP地址：

networks:
  my-docker-network:
    ipv4_address: 192.168.3.2

另外，应该足以确保在此处定义了已知的网络以在.NET Core中指定其网关。