在网页里怎么显示icon的返回类型？（调用文件的图标，怎么在网页里显示出来）

找到了这样一段代码：
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
        }
        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);
        }
    }
}请问怎么在网页里把这个文件的图标显示出来？
我是这样写的
ExtractIcon.GetIcon("D:\\wwwroot\\web.gif", true);
但是什么也没有显示，请教该怎么做？