C# Signature:

[DllImport("shell32.dll")]
static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes,
   out SHFILEINFO psfi, uint cbFileInfo, uint uFlags);

User-Defined Types:

None.

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

    // From http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=uMD%23VHmqBHA.2368%40tkmsftngp03&rnum=4
    using System;
    using System.Runtime.InteropServices;
    using System.Drawing;

    /// <summary>
    /// Summary description for ExtractIcon.
    /// </summary>
    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
    }

    /// <summary>
    /// Get the associated Icon for a file or application, this method always returns
    /// an icon.  If the strPath is invalid or there is no idonc the default icon is returned
    /// </summary>
    /// <param name="strPath">full path to the file</param>
    /// <param name="bSmall">if true, the 16x16 icon is returned otherwise the 32x32</param>
    /// <returns></returns>
    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);
    }
    }

Alternative Managed API:

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