从Windows Mobile应用程序获取文件的图标

Question

我正在使用C＃开发Windows Mobile应用程序6.我需要获取文件的图标，但我不知道如何做到这一点= P。

有办法得到它吗？

Answer 1

是的，虽然它并不痛苦，并且需要使用PInvoke。这是我如何做到的。 （WinApi是一个辅助静态类，它包含PInvoke外部函数定义以及一些必需的常量，其中还有很多内容，但我删除了与获取文件图标无关的内容。）

using System; 
using System.IO; 
using System.Collections.Generic; 
using System.Text; 
using System.Runtime.InteropServices; 
using System.Drawing; 

namespace ExtendedCF { 
    public static class WinApi 
    { 
     #region Icons 
     [DllImport("coredll.dll")] 
     public static extern bool DestroyIcon(IntPtr hIcon); 
     #endregion 

     #region SHGetFileInfo 
     [DllImport("coredll.dll", CharSet = CharSet.Auto)] 
     public static extern int SHGetFileInfo(
      string pszPath, 
      int dwFileAttributes, 
      out SHFILEINFO psfi, 
      uint cbfileInfo, 
      SHGFI uFlags); 

     [Flags] 
     public enum SHGFI : int 
     { 
      /// <summary>get icon</summary> 
      Icon = 0x000000100, 
      /// <summary>get display name</summary> 
      DisplayName = 0x000000200, 
      /// <summary>get type name</summary> 
      TypeName = 0x000000400, 
      /// <summary>get attributes</summary> 
      Attributes = 0x000000800, 
      /// <summary>get icon location</summary> 
      IconLocation = 0x000001000, 
      /// <summary>return exe type</summary> 
      ExeType = 0x000002000, 
      /// <summary>get system icon index</summary> 
      SysIconIndex = 0x000004000, 
      /// <summary>put a link overlay on icon</summary> 
      LinkOverlay = 0x000008000, 
      /// <summary>show icon in selected state</summary> 
      Selected = 0x000010000, 
      /// <summary>get only specified attributes</summary> 
      Attr_Specified = 0x000020000, 
      /// <summary>get large icon</summary> 
      LargeIcon = 0x000000000, 
      /// <summary>get small icon</summary> 
      SmallIcon = 0x000000001, 
      /// <summary>get open icon</summary> 
      OpenIcon = 0x000000002, 
      /// <summary>get shell size icon</summary> 
      ShellIconSize = 0x000000004, 
      /// <summary>pszPath is a pidl</summary> 
      PIDL = 0x000000008, 
      /// <summary>use passed dwFileAttribute</summary> 
      UseFileAttributes = 0x000000010, 
      /// <summary>apply the appropriate overlays</summary> 
      AddOverlays = 0x000000020, 
      /// <summary>Get the index of the overlay in the upper 8 bits of the iIcon</summary> 
      OverlayIndex = 0x000000040, 
     } 

     /// <summary>Maximal Length of unmanaged Windows-Path-strings</summary> 
     private const int MAX_PATH = 260; 
     /// <summary>Maximal Length of unmanaged Typename</summary> 
     private const int MAX_TYPE = 80; 

     [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)] 
     public struct SHFILEINFO 
     { 
      public SHFILEINFO(bool dummy) 
      { 
       hIcon = IntPtr.Zero; 
       iIcon = 0; 
       dwAttributes = 0; 
       szDisplayName = ""; 
       szTypeName = ""; 
      } 
      public IntPtr hIcon; 
      public int iIcon; 
      public uint dwAttributes; 
      [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH)] 
      public string szDisplayName; 
      [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_TYPE)] 
      public string szTypeName; 
     }; 

     #endregion 
    } 
    public static class Utils 
    { 
     #region GetFileIcon and GetFolderIcon 
     /// <summary> 
     /// Get the associated Icon for a file or application. Always returns 
     /// an icon. If the filePath is invalid, the default icon for files of such type is returned. 
     /// </summary> 
     /// <param name="filePath">full path to the file</param> 
     /// <param name="bSmall">if true, return the 16x16 icon; otherwise, the 32x32 icon</param> 
     /// <returns></returns> 
     private static Icon GetIcon(string filePath, bool bFolder, bool bSmall) 
     { 
      WinApi.SHFILEINFO info = new WinApi.SHFILEINFO(true); 
      int cbFileInfo = Marshal.SizeOf(info); 
      WinApi.SHGFI flags = WinApi.SHGFI.Icon | WinApi.SHGFI.UseFileAttributes; 
      if (bSmall) 
       flags |= WinApi.SHGFI.SmallIcon; 
      else 
       flags |= WinApi.SHGFI.LargeIcon; 

      int fileAttributes = 0; 
      if (bFolder) 
      { 
       fileAttributes = (int)FileAttributes.Directory; 
      } 

      WinApi.SHGetFileInfo(filePath, fileAttributes, out info, (uint)cbFileInfo, flags); 
      Icon rv = (Icon)Icon.FromHandle(info.hIcon).Clone(); 
      WinApi.DestroyIcon(info.hIcon); 
      return rv; 
     } 
     private static Icon GetIcon(string filePath, bool bFolder) 
     { 
      return GetIcon(filePath, bFolder, false); 
     } 
     public static Icon GetFileIcon(string filePath) 
     { 
      return GetIcon(filePath, false); 
     } 
     public static Icon GetFolderIcon(string folderPath) 
     { 
      return GetIcon(folderPath, true); 
     } 
     public static Icon GetFileIcon(string filePath, bool bSmall) 
     { 
      return GetIcon(filePath, false, bSmall); 
     } 
     public static Icon GetFolderIcon(string folderPath, bool bSmall) 
     { 
      return GetIcon(folderPath, true, bSmall); 
     } 
     #endregion 
    } 
}