Get a small or large Icon with an easy C# function call that returns a 32x32 or 16x16 icon.

ShellIcon.cs

// -----------------------------------------------------------------------
// <copyright file="ShellIcon.cs" company="Mauricio DIAZ ORLICH (madd0@madd0.com)">
//   Distributed under Microsoft Public License (MS-PL).
//   http://www.opensource.org/licenses/MS-PL
// </copyright>
// -----------------------------------------------------------------------

/// <summary>
/// Get a small or large Icon with an easy C# function call
/// that returns a 32x32 or 16x16 System.Drawing.Icon depending on which function you call
/// either GetSmallIcon(string fileName) or GetLargeIcon(string fileName)
/// </summary>
public static class ShellIcon
{
    #region Interop constants

    private const uint FILE_ATTRIBUTE_NORMAL = 0x80;
    private const uint FILE_ATTRIBUTE_DIRECTORY = 0x10;

    #endregion

    #region Interop data types

    [StructLayout(LayoutKind.Sequential)]
    private 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;
    }

    [Flags]
    private 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,
    }

    #endregion

    private class Win32
    {
        [DllImport("shell32.dll")]
        public static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbSizeFileInfo, uint uFlags);

        [DllImport("User32.dll")]
        public static extern int DestroyIcon(IntPtr hIcon);

    }
    
    public static Icon GetSmallFolderIcon()
    {
        return GetIcon("folder", SHGFI.SmallIcon | SHGFI.UseFileAttributes, true);
    }

    public static Icon GetLargeFolderIcon()
    {
        return GetIcon("folder", SHGFI.LargeIcon | SHGFI.UseFileAttributes, true);
    }

    public static Icon GetSmallIcon(string fileName)
    {
        return GetIcon(fileName, SHGFI.SmallIcon);
    }

    public static Icon GetLargeIcon(string fileName)
    {
        return GetIcon(fileName, SHGFI.LargeIcon);
    }

    public static Icon GetSmallIconFromExtension(string extension)
    {
        return GetIcon(extension, SHGFI.SmallIcon | SHGFI.UseFileAttributes);
    }

    public static Icon GetLargeIconFromExtension(string extension)
    {
        return GetIcon(extension, SHGFI.LargeIcon | SHGFI.UseFileAttributes);
    }

    private static Icon GetIcon(string fileName, SHGFI flags, bool isFolder = false)
    {
        SHFILEINFO shinfo = new SHFILEINFO();

        IntPtr hImgSmall = Win32.SHGetFileInfo(fileName, isFolder ? FILE_ATTRIBUTE_DIRECTORY : FILE_ATTRIBUTE_NORMAL, ref shinfo, (uint)Marshal.SizeOf(shinfo), (uint)(SHGFI.Icon | flags));

        Icon icon = (Icon)System.Drawing.Icon.FromHandle(shinfo.hIcon).Clone();
        Win32.DestroyIcon(shinfo.hIcon);
        return icon;
    }
}

I want to have Large Icon size 64x64
Please help me!