C#获取文件图标

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

        /// <summary>  
        /// 返回系统设置的图标  
        /// </summary>  
        /// <param name="pszPath">文件路径 如果为""  返回文件夹的</param>  
        /// <param name="dwFileAttributes">0</param>  
        /// <param name="psfi">结构体</param>  
        /// <param name="cbSizeFileInfo">结构体大小</param>  
        /// <param name="uFlags">枚举类型</param>  
        /// <returns>-1失败</returns>  
        [DllImport("shell32.dll")]
        public static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref   SHFILEINFO psfi, uint cbSizeFileInfo, uint uFlags);

        public enum SHGFI
        {
            SHGFI_ICON = 0x100,
            SHGFI_LARGEICON = 0x0,
            SHGFI_USEFILEATTRIBUTES = 0x10
        }


        /// <summary>  
        /// 获取文件图标 
        /// </summary>  
        /// <param name="p_Path">文件全路径</param>  
        /// <returns>图标</returns>  
        public static Icon GetFileIcon(string p_Path)
        {
            Icon _Icon = Properties.Resources.fileIco;
            try
            {
                SHFILEINFO _SHFILEINFO = new SHFILEINFO();
                IntPtr _IconIntPtr = SHGetFileInfo(p_Path, 0, ref _SHFILEINFO, (uint)Marshal.SizeOf(_SHFILEINFO), (uint)(SHGFI.SHGFI_ICON | SHGFI.SHGFI_LARGEICON | SHGFI.SHGFI_USEFILEATTRIBUTES));
                if (_IconIntPtr.Equals(IntPtr.Zero)) return null;
                _Icon = System.Drawing.Icon.FromHandle(_SHFILEINFO.hIcon);
            }
            catch
            {
            }
            return _Icon;
        }

//调用的时候这么调用
Icon tempIcon = GetFileIcon(fileName);