public static Bitmap ConvertIco2Bmp(Icon icon, Brush backBrush)
{
Bitmap bmp;
// Declare the raw handles
IntPtr hdcDisplay = IntPtr.Zero, hdcMem = IntPtr.Zero, hBitmap = IntPtr.Zero;
try
{
// Get the display's Device Context so that the generated bitmaps were compatible
hdcDisplay = Win32Declarations.CreateDC("DISPLAY", null, null, IntPtr.Zero);
if (hdcDisplay == IntPtr.Zero)
{
throw new Exception("Failed to get the display device context.");
}
// Create a pixel format compatible device context, and a bitmap to draw into using this context
hdcMem = Win32Declarations.CreateCompatibleDC(hdcDisplay);
if (hdcMem == IntPtr.Zero)
{
throw new Exception("Could not cerate a compatible device context.");
}
hBitmap = Win32Declarations.CreateCompatibleBitmap(hdcDisplay, icon.Width, icon.Height);
if (hBitmap == IntPtr.Zero)
{
throw new Exception("Could not cerate a compatible offscreen bitmap.");
}
Win32Declarations.SelectObject(hdcMem, hBitmap);
// Attach a GDI+ Device Context to the offscreen facility, and render the scene
using (Graphics gm = Graphics.FromHdc(hdcMem))
{
gm.FillRectangle(backBrush, 0, 0, icon.Width, icon.Height);
gm.DrawIcon(icon, 0, 0);
}
// Wrap the offscreen bitmap into a .NET bitmap in order to save it
bmp = Image.FromHbitmap(hBitmap);
}
finally
{
// Cleanup the native resources in use
if (hBitmap != IntPtr.Zero)
{
Win32Declarations.DeleteObject(hBitmap);
}
if (hdcMem != IntPtr.Zero)
{
Win32Declarations.DeleteDC(hdcMem);
}
if (hdcDisplay != IntPtr.Zero)
{
Win32Declarations.DeleteDC(hdcDisplay);
}
}
return(bmp);
}
