C#取回文件的默认图标.

using System;

using System.Runtime.InteropServices;

using System.Drawing;

 

namespace WindowsAppTmp

{

    public class ExtractIcon

    {

        [DllImport("Shell32.dll")]

        private static extern int SHGetFileInfo

          (

          string pszPath,

          uint dwFileAttributes,

          out   SHFILEINFO psfi,

          uint cbfileInfo,

          SHGFI uFlags

          );

 

        [StructLayout(LayoutKind.Sequential)]

        private struct SHFILEINFO

        {

            public SHFILEINFO(bool b)

            {

                hIcon = IntPtr.Zero; iIcon = 0; dwAttributes = 0; szDisplayName = ""; szTypeName = "";

            }

            public IntPtr hIcon;

            public int iIcon;

            public uint dwAttributes;

            [MarshalAs(UnmanagedType.LPStr, SizeConst = 260)]

            public string szDisplayName;

            [MarshalAs(UnmanagedType.LPStr, SizeConst = 80)]

            public string szTypeName;

        };

 

        private ExtractIcon()

        {

        }

 

        private enum SHGFI

        {

            SmallIcon = 0x00000001,

            LargeIcon = 0x00000000,

            Icon = 0x00000100,

            DisplayName = 0x00000200,

            Typename = 0x00000400,

            SysIconIndex = 0x00004000,

            UseFileAttributes = 0x00000010

        }

 

        //取回小图标

 

        public static Icon GetIcon(string strPath, bool bSmall)

        {

            SHFILEINFO info = new SHFILEINFO(true);

            int cbFileInfo = Marshal.SizeOf(info);

            SHGFI flags;

            if (bSmall)

                flags = SHGFI.Icon | SHGFI.SmallIcon | SHGFI.UseFileAttributes;

            else

                flags = SHGFI.Icon | SHGFI.LargeIcon | SHGFI.UseFileAttributes;

 

            SHGetFileInfo(strPath, 256, out   info, (uint)cbFileInfo, flags);

            return Icon.FromHandle(info.hIcon);

        }

    }

}

 

使用方法：

 

 

        private void button1_Click(object sender, EventArgs e)

        {

            string Path = @"D:/我的文档/Visual Studio 2005/Projects/AllTest/SetHotKey/SetHotKey/bin/Debug/SetHotKey.exe";

            //Icon tempIcon = ExtractIcon.GetIcon(Path, true);//取回的是小图标
            //使用.net库里面的类也可以,不过取回的总是大图标.

            Icon tempIcon = System.Drawing.Icon.ExtractAssociatedIcon(Path);             this.Icon = tempIcon;

        }