文件夹中的文件计数

如何使用带有C＃的ASP.NET从文件夹中获取文件数量？

System.IO.Directory myDir = GetMyDirectoryForTheExample();
int count = myDir.GetFiles().Length;

您可以使用Directory.GetFiles方法

另请参见Directory.GetFiles方法（字符串，字符串，SearchOption）

您可以在此重载中指定搜索选项。

TopDirectoryOnly：搜索中仅包含当前目录。

AllDirectories：在搜索操作中包括当前目录和所有子目录。此选项包括重新解析点，例如搜索中的安装驱动器和符号链接。

// searches the current directory and sub directory
int fCount = Directory.GetFiles(path, "*", SearchOption.AllDirectories).Length;
// searches the current directory
int fCount = Directory.GetFiles(path, "*", SearchOption.TopDirectoryOnly).Length;

最好的方法是使用LINQ：

var fileCount = (from file in Directory.EnumerateFiles(@"H:\iPod_Control\Music", "*.mp3", SearchOption.AllDirectories)
                        select file).Count();

System.IO.DirectoryInfo dir = new System.IO.DirectoryInfo("SourcePath");
int count = dir.GetFiles().Length;

您可以使用它。

从目录读取PDF文件：

var list = Directory.GetFiles(@"C:\ScanPDF", "*.pdf");
if (list.Length > 0)
{

}

.NET方法Directory.GetFiles（dir）或DirectoryInfo.GetFiles（）对于仅获取总文件数而言不是很快。如果您大量使用此文件计数方法，请考虑直接使用WinAPI，这样可以节省大约50％的时间。

这是WinAPI方法，其中封装了对C＃方法的WinAPI调用：

int GetFileCount(string dir, bool includeSubdirectories = false)

完整的代码：

[Serializable, StructLayout(LayoutKind.Sequential)]
private struct WIN32_FIND_DATA
{
    public int dwFileAttributes;
    public int ftCreationTime_dwLowDateTime;
    public int ftCreationTime_dwHighDateTime;
    public int ftLastAccessTime_dwLowDateTime;
    public int ftLastAccessTime_dwHighDateTime;
    public int ftLastWriteTime_dwLowDateTime;
    public int ftLastWriteTime_dwHighDateTime;
    public int nFileSizeHigh;
    public int nFileSizeLow;
    public int dwReserved0;
    public int dwReserved1;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
    public string cFileName;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 14)]
    public string cAlternateFileName;
}

[DllImport("kernel32.dll")]
private static extern IntPtr FindFirstFile(string pFileName, ref WIN32_FIND_DATA pFindFileData);
[DllImport("kernel32.dll")]
private static extern bool FindNextFile(IntPtr hFindFile, ref WIN32_FIND_DATA lpFindFileData);
[DllImport("kernel32.dll")]
private static extern bool FindClose(IntPtr hFindFile);

private static readonly IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1);
private const int FILE_ATTRIBUTE_DIRECTORY = 16;

private int GetFileCount(string dir, bool includeSubdirectories = false)
{
    string searchPattern = Path.Combine(dir, "*");

    var findFileData = new WIN32_FIND_DATA();
    IntPtr hFindFile = FindFirstFile(searchPattern, ref findFileData);
    if (hFindFile == INVALID_HANDLE_VALUE)
        throw new Exception("Directory not found: " + dir);

    int fileCount = 0;
    do
    {
        if (findFileData.dwFileAttributes != FILE_ATTRIBUTE_DIRECTORY)
        {
            fileCount++;
            continue;
        }

        if (includeSubdirectories && findFileData.cFileName != "." && findFileData.cFileName != "..")
        {
            string subDir = Path.Combine(dir, findFileData.cFileName);
            fileCount += GetFileCount(subDir, true);
        }
    }
    while (FindNextFile(hFindFile, ref findFileData));

    FindClose(hFindFile);

    return fileCount;
}

当我在计算机上搜索包含13000个文件的文件夹时-平均：110ms

int fileCount = GetFileCount(searchDir, true); // using WinAPI

.NET内置方法：Directory.GetFiles（dir）-平均：230ms

int fileCount = Directory.GetFiles(searchDir, "*", SearchOption.AllDirectories).Length;

注意：这两种方法的首次运行速度将分别降低60％-100％，因为硬盘驱动器需要更长的时间来定位扇区。我猜以后的调用将被Windows半缓存。

int fileCount = Directory.GetFiles(path, "*.*", SearchOption.AllDirectories).Length; // Will Retrieve count of all files in directry and sub directries

int fileCount = Directory.GetFiles(path, "*.*", SearchOption.TopDirectory).Length; // Will Retrieve count of all files in directry but not sub directries

int fileCount = Directory.GetFiles(path, "*.xml", SearchOption.AllDirectories).Length; // Will Retrieve count of files XML extension in directry and sub directries

尝试使用以下代码来获取文件夹中文件的数量

string strDocPath = Server.MapPath('Enter your path here'); 
int docCount = Directory.GetFiles(strDocPath, "*", 
SearchOption.TopDirectoryOnly).Length;

int filesCount = Directory.EnumerateFiles(Directory).Count();

要使用LINQ获得某些类型扩展的数量，可以使用以下简单代码：

Dim exts() As String = {".docx", ".ppt", ".pdf"}

Dim query = (From f As FileInfo In directory.GetFiles()).Where(Function(f) exts.Contains(f.Extension.ToLower()))

Response.Write(query.Count())