public static Bitmap GetDesktopImage()
{
IntPtr dC = PlatformInvokeUSER32.GetDC(PlatformInvokeUSER32.GetDesktopWindow());
IntPtr intPtr = PlatformInvokeGDI32.CreateCompatibleDC(dC);
SIZE sIZE;
sIZE.cx = PlatformInvokeUSER32.GetSystemMetrics(0);
sIZE.cy = PlatformInvokeUSER32.GetSystemMetrics(1);
IntPtr intPtr2 = PlatformInvokeGDI32.CreateCompatibleBitmap(dC, sIZE.cx, sIZE.cy);
Bitmap result;
if (intPtr2 != IntPtr.Zero)
{
IntPtr bmp = PlatformInvokeGDI32.SelectObject(intPtr, intPtr2);
PlatformInvokeGDI32.BitBlt(intPtr, 0, 0, sIZE.cx, sIZE.cy, dC, 0, 0, 13369376);
PlatformInvokeGDI32.SelectObject(intPtr, bmp);
PlatformInvokeGDI32.DeleteDC(intPtr);
PlatformInvokeUSER32.ReleaseDC(PlatformInvokeUSER32.GetDesktopWindow(), dC);
Bitmap bitmap = Image.FromHbitmap(intPtr2);
PlatformInvokeGDI32.DeleteObject(intPtr2);
GC.Collect();
result = bitmap;
}
else
{
result = null;
}
return(result);
}
public static Bitmap GetDesktopImage()
{
//In size variable we shall keep the size of the screen.
SIZE size;
//Variable to keep the handle to bitmap.
IntPtr hBitmap;
//Here we get the handle to the desktop device context.
IntPtr hDC = PlatformInvokeUSER32.GetDC(PlatformInvokeUSER32.GetDesktopWindow());
//Here we make a compatible device context in memory for screen device context.
IntPtr hMemDC = PlatformInvokeGDI32.CreateCompatibleDC(hDC);
//We pass SM_CXSCREEN constant to GetSystemMetrics to get the X coordinates of screen.
size.cx = PlatformInvokeUSER32.GetSystemMetrics(PlatformInvokeUSER32.SM_CXSCREEN);
//We pass SM_CYSCREEN constant to GetSystemMetrics to get the Y coordinates of screen.
size.cy = PlatformInvokeUSER32.GetSystemMetrics(PlatformInvokeUSER32.SM_CYSCREEN);
//We create a compatible bitmap of screen size using screen device context.
hBitmap = PlatformInvokeGDI32.CreateCompatibleBitmap(hDC, size.cx, size.cy);
//As hBitmap is IntPtr we can not check it against null. For this purspose IntPtr.Zero is used.
if (hBitmap != IntPtr.Zero)
{
//Here we select the compatible bitmap in memeory device context and keeps the refrence to Old bitmap.
IntPtr hOld = (IntPtr)PlatformInvokeGDI32.SelectObject(hMemDC, hBitmap);
//We copy the Bitmap to the memory device context.
PlatformInvokeGDI32.BitBlt(hMemDC, 0, 0, size.cx, size.cy, hDC, 0, 0, PlatformInvokeGDI32.SRCCOPY);
//We select the old bitmap back to the memory device context.
PlatformInvokeGDI32.SelectObject(hMemDC, hOld);
//We delete the memory device context.
PlatformInvokeGDI32.DeleteDC(hMemDC);
//We release the screen device context.
PlatformInvokeUSER32.ReleaseDC(PlatformInvokeUSER32.GetDesktopWindow(), hDC);
//Image is created by Image bitmap handle and stored in local variable.
Bitmap bmp = System.Drawing.Image.FromHbitmap(hBitmap);
//Release the memory to avoid memory leaks.
PlatformInvokeGDI32.DeleteObject(hBitmap);
//This statement runs the garbage collector manually.
GC.Collect();
//Return the bitmap
return(bmp);
}
//If hBitmap is null retunrn null.
return(null);
}
