/// <summary>
/// Sets the bitmap to use for this form.
/// </summary>
private void SetBitmap( Bitmap bitmap )
{
// Collect some variables we'll use to render.
IntPtr screenDc = GetDC( IntPtr.Zero );
IntPtr memDc = CreateCompatibleDC( screenDc );
IntPtr hBitmap = IntPtr.Zero;
IntPtr oldBitmap = IntPtr.Zero;
try
{
hBitmap = bitmap.GetHbitmap( Color.FromArgb(0) );
oldBitmap = SelectObject( memDc, hBitmap );
W32Size size = new W32Size( bitmap.Width, bitmap.Height );
W32Point pointSource = new W32Point( 0, 0 );
W32Point topPos = new W32Point( this.Left, this.Top );
BLENDFUNCTION blend = new BLENDFUNCTION();
blend.BlendOp = 0x00; // AC_SRC_OVER
blend.BlendFlags = 0;
blend.SourceConstantAlpha = 255;
blend.AlphaFormat = 0x01; // AC_SRC_ALPHA
lock( this )
if( !Disposing )
UpdateLayeredWindow(
Handle,
screenDc,
ref topPos,
ref size,
memDc,
ref pointSource,
0,
ref blend,
(Int32) 0x00000002 // ULW_ALPHA
);
}
catch { /* Ignore errors */ }
finally
{
// Clean things up...
ReleaseDC( IntPtr.Zero, screenDc );
if( hBitmap != IntPtr.Zero )
{
SelectObject( memDc, oldBitmap );
DeleteObject( hBitmap );
}
DeleteDC( memDc );
}
}
private static extern W32Bool UpdateLayeredWindow(
IntPtr hwnd,
IntPtr hdcDst,
ref W32Point pptDst,
ref W32Size psize,
IntPtr hdcSrc,
ref W32Point pprSrc,
Int32 crKey,
ref BLENDFUNCTION pblend,
Int32 dwFlags
);
