一个获取文件的ICON类

using System;
using System.Runtime.InteropServices;
namespace Tools.GUI
{
/// <summary>
/// Description r閟um閑 de System.Drawing.Icon.
/// </summary>
public class CIcon
{
private const UInt32 SHGFI_ICON = 0x100;
private const UInt32 SHGFI_LARGEICON = 0x0; // 'Large icon
private const UInt32 SHGFI_SMALLICON = 0x1; // 'Small icon

[DllImport("shell32.dll")]
private static extern IntPtr SHGetFileInfo(string pszPath,
UInt32 dwFileAttributes, ref SHFILEINFO psfi, UInt32 cbSizeFileInfo,
UInt32 uFlags);

[StructLayout(LayoutKind.Sequential)]
private struct SHFILEINFO
{
public IntPtr hIcon;
public IntPtr iIcon;
public UInt32 dwAttributes;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public string szDisplayName;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
public string szTypeName;
};

public static System.Drawing.Icon GetIcon(string filename,bool
b_large_icon)
{
UInt32 icon_size;
if (b_large_icon)
icon_size=SHGFI_LARGEICON;
else
icon_size=SHGFI_SMALLICON;

IntPtr hImgSmall;
SHFILEINFO shinfo = new SHFILEINFO();

hImgSmall = SHGetFileInfo(filename, 0, ref shinfo,(UInt32)Marshal.SizeOf(shinfo),SHGFI_ICON |icon_size);
System.Drawing.Icon myIcon = System.Drawing.Icon.FromHandle(shinfo.hIcon);

return myIcon;
}

}
}