Determine color of a pixel in a winforms application

Question

I\'d like to be able to determine the backgroundcolor of a winform at a certain point on the screen, so I can take some action depending on that particular color. Sadly the

Answer 1

Assuming you want to stay away from the Win32 API, you can use Graphics.CopyFromScreen() to draw the content of your screen to a Bitmap object. From there, you just need to use Bitmap.GetPixel() to retrieve a Color object with the right color.

Here's some code you can use to retrieve the complete desktop (works with multiple monitors):

public Image GetScreenshot()
{
    int screenWidth = Convert.ToInt32(System.Windows.SystemParameters.VirtualScreenWidth);
    int screenHeight = Convert.ToInt32(SystemParameters.VirtualScreenHeight);
    int screenLeft = Convert.ToInt32(SystemParameters.VirtualScreenLeft);
    int screenTop = Convert.ToInt32(SystemParameters.VirtualScreenTop);

    Image imgScreen = new Bitmap(screenWidth, screenHeight);
    using (Bitmap bmp = new Bitmap(screenWidth, screenHeight, PixelFormat.Format32bppArgb))
    using (Graphics g = Graphics.FromImage(bmp))
    using (Graphics gr = Graphics.FromImage(imgScreen))
    {
        g.CopyFromScreen(screenLeft, screenTop, 0, 0, new Size(screenWidth, screenHeight));
        gr.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
        gr.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
        gr.DrawImage(bmp, new Rectangle(0, 0, screenWidth, screenHeight));
    }

    return imgScreen;
}