protected Bitmap GetScreenPortionAsImage(IntPtr displayContext, int positionX, int positionY, int width,
int height)
{
IntPtr displayCompatibleContext = WindowInvoker.CreateCompatibleDC(displayContext);
IntPtr displayCompatibleBitmap =
WindowInvoker.CreateCompatibleBitmap(displayContext, width, height);
// Select the new bitmap for future operations on our context
IntPtr previousBitmap = WindowInvoker.SelectObject(displayCompatibleContext, displayCompatibleBitmap);
// Copy the colour data from our desktop (and anything covering it) to our screenshot context
bool isScreengrabSuccessful = WindowInvoker.BitBlt(displayCompatibleContext, 0, 0, width,
height, displayContext, positionX, positionY,
CopyPixelOperation.SourceCopy | CopyPixelOperation.CaptureBlt);
Bitmap screenPortionImage = isScreengrabSuccessful ? Image.FromHbitmap(displayCompatibleBitmap) : null;
// Restore our previous image selection
WindowInvoker.SelectObject(displayCompatibleContext, previousBitmap);
// Clean up our created objects so we're not hogging resources
WindowInvoker.DeleteObject(displayCompatibleBitmap);
WindowInvoker.DeleteDC(displayCompatibleContext);
return(screenPortionImage);
}
public Bitmap GetPortionAsImage(int positionX, int positionY, int width, int height)
{
IntPtr desktopContext = WindowInvoker.CreateDC("DISPLAY", null, null, IntPtr.Zero);
Bitmap screenPortionImage = GetScreenPortionAsImage(desktopContext, positionX, positionY, width, height);
WindowInvoker.DeleteDC(desktopContext);
return(screenPortionImage);
}