Extract Bitmap from DLL for use in PowerShell Script - powershell

Question

I'm in the process of building a little utility using powershell and have spent a good deal of time teaching myself about building windows forms and controls using powershell. In order to keep my deployment to a small footprint I have packaged all of my graphics icons (.ico) and images (.bmp) in a dynamically linked library (*.dll) using a third party utilty (greenfish icon editor pro, which I highly recommend).
The problem that I have now is that I can't load the assembly because the resulting *.dll is missing a manifest. I've searched all over but was unable to find any concise answer on how to access the resource without using the add-type cmdlet to load the *.dll.

Answer 1

I was able to find a way to load icons from a dll in an answer to this post from Kazun. Then utilizing technet I was able to find a corresponding entry point in the dll for a method to extract a bitmap. See my kludged together script below which combines both the IconExtractor and my newly created BitmapExtractor classes.
$code = #"
using System;
using System.Drawing;
using System.Runtime.InteropServices;
namespace System {
public class IconExtractor { #Credit to Kazun from https://social.technet.microsoft.com/Forums/windows/en-US/16444c7a-ad61-44a7-8c6f-b8d619381a27/using-icons-in-powershell-scripts?forum=winserverpowershell
public static Icon Extract(string file, int number, bool largeIcon) {
IntPtr large;
IntPtr small;
ExtractIconEx(file, number, out large, out small, 1);
try {
return Icon.FromHandle(largeIcon ? large : small);
} catch {
return null;
}
}
[DllImport("Shell32.dll", EntryPoint = "ExtractIconExW", CharSet = CharSet.Unicode, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
private static extern int ExtractIconEx(string sFile, int iIndex, out IntPtr piLargeVersion, out IntPtr piSmallVersion, int amountIcons);
}
public class BitmapExtractor { #Credit to Chad Estes (chadwestes#gmail.com)
public static Bitmap Extract(string file, string resourceID) {
IntPtr hModule = LoadLibraryEx(file,IntPtr.Zero,0x00000020);
Bitmap bmp = null;
IntPtr hBitmap = IntPtr.Zero;
try {
if (hModule != IntPtr.Zero) {
hBitmap = LoadBitmap(hModule, resourceID);
if (hBitmap != IntPtr.Zero) {
bmp = Bitmap.FromHbitmap(hBitmap);
}
}
} catch {
bmp = null;
} finally {
DeleteObject(hBitmap);
FreeLibrary(hModule);
}
return bmp;
}
[DllImport("kernel32.dll", SetLastError = true)]
static extern IntPtr LoadLibraryEx(string lpFileName, IntPtr hReservedNull, uint dwFlags);
[DllImport("kernel32.dll", SetLastError=true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool FreeLibrary(IntPtr hModule);
[DllImport("user32.dll")]
static extern IntPtr LoadBitmap(IntPtr hInstance, string lpBitmapName);
[DllImport("gdi32.dll", EntryPoint="DeleteObject", CharSet = CharSet.Unicode, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
private static extern bool DeleteObject(IntPtr hBitmap);
}
}
"#
Add-Type -TypeDefinition $code -ReferencedAssemblies System.Drawing
$myImage = [System.BitmapExtractor]::Extract("C:\SomePath\Some.dll", "LOGO")
$myIcon = [System.IconExtractor]::Extract("C:\SomePath\Some.dll", 1, $true)