如何在 .NET 中獲取文件副檔名的描述

你好，

Windows 提供文件副檔名的描述，例如 .cpl 文件的“控制面板項”和 .daa 文件的“PowerISO 文件”。有什麼方法可以在 .NET 中獲取這些數據？我使用 C#，但可以閱讀所有其他 .NET 語言。還有一種方法可以獲取擴展的預設圖示嗎？任何幫助，將不勝感激。

提前致謝

您可以使用SHGetFileInfoAPI 來獲取該資訊。這是一個包裝器方法：

   public static string GetFileTypeDescription(string fileNameOrExtension)
   {
       SHFILEINFO shfi;
       if (IntPtr.Zero != SHGetFileInfo(
                           fileNameOrExtension,
                           FILE_ATTRIBUTE_NORMAL,
                           out shfi,
                           (uint)Marshal.SizeOf(typeof(SHFILEINFO)),
                           SHGFI_USEFILEATTRIBUTES | SHGFI_TYPENAME))
       {
           return shfi.szTypeName;
       }
       return null;
   }

   [DllImport("shell32")]
   private static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, out SHFILEINFO psfi, uint cbFileInfo, uint flags);

   [StructLayout(LayoutKind.Sequential)]
   private struct SHFILEINFO
   {
       public IntPtr hIcon;
       public int iIcon;
       public uint dwAttributes;
       [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
       public string szDisplayName;
       [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
       public string szTypeName;
   }

   private const uint FILE_ATTRIBUTE_READONLY = 0x00000001;
   private const uint FILE_ATTRIBUTE_HIDDEN = 0x00000002;
   private const uint FILE_ATTRIBUTE_SYSTEM = 0x00000004;
   private const uint FILE_ATTRIBUTE_DIRECTORY = 0x00000010;
   private const uint FILE_ATTRIBUTE_ARCHIVE = 0x00000020;
   private const uint FILE_ATTRIBUTE_DEVICE = 0x00000040;
   private const uint FILE_ATTRIBUTE_NORMAL = 0x00000080;
   private const uint FILE_ATTRIBUTE_TEMPORARY = 0x00000100;
   private const uint FILE_ATTRIBUTE_SPARSE_FILE = 0x00000200;
   private const uint FILE_ATTRIBUTE_REPARSE_POINT = 0x00000400;
   private const uint FILE_ATTRIBUTE_COMPRESSED = 0x00000800;
   private const uint FILE_ATTRIBUTE_OFFLINE = 0x00001000;
   private const uint FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = 0x00002000;
   private const uint FILE_ATTRIBUTE_ENCRYPTED = 0x00004000;
   private const uint FILE_ATTRIBUTE_VIRTUAL = 0x00010000;

   private const uint SHGFI_ICON = 0x000000100;     // get icon
   private const uint SHGFI_DISPLAYNAME = 0x000000200;     // get display name
   private const uint SHGFI_TYPENAME = 0x000000400;     // get type name
   private const uint SHGFI_ATTRIBUTES = 0x000000800;     // get attributes
   private const uint SHGFI_ICONLOCATION = 0x000001000;     // get icon location
   private const uint SHGFI_EXETYPE = 0x000002000;     // return exe type
   private const uint SHGFI_SYSICONINDEX = 0x000004000;     // get system icon index
   private const uint SHGFI_LINKOVERLAY = 0x000008000;     // put a link overlay on icon
   private const uint SHGFI_SELECTED = 0x000010000;     // show icon in selected state
   private const uint SHGFI_ATTR_SPECIFIED = 0x000020000;     // get only specified attributes
   private const uint SHGFI_LARGEICON = 0x000000000;     // get large icon
   private const uint SHGFI_SMALLICON = 0x000000001;     // get small icon
   private const uint SHGFI_OPENICON = 0x000000002;     // get open icon
   private const uint SHGFI_SHELLICONSIZE = 0x000000004;     // get shell size icon
   private const uint SHGFI_PIDL = 0x000000008;     // pszPath is a pidl
   private const uint SHGFI_USEFILEATTRIBUTES = 0x000000010;     // use passed dwFileAttribute

（大多數常量實際上並未在該程式碼中使用，但無論如何我都會將它們放入以防您想使程式碼適應您的特定需求）

引用自：https://stackoverflow.com/questions/3780028