C# print screen predefined region

Question

I want to capture only a predefined region of the application, for example I want to print screen only the group box. I changed this.bounds to groupbox.bounds but it doesn't work. It captures other regions but not the group box. Any ideas? The codes are:

// Set the bitmap object to the size of the screen
    bmpScreenshot = new Bitmap(this.Bounds.Width, this.Bounds.Height, PixelFormat.Format32bppArgb);
    // Create a graphics object from the bitmap
    gfxScreenshot = Graphics.FromImage(bmpScreenshot);
    // Take the screenshot from the upper left corner to the right bottom corner
    gfxScreenshot.CopyFromScreen(this.Bounds.X, this.Bounds.Y, 0, 0, this.Bounds.Size, CopyPixelOperation.SourceCopy);

SaveFileDialog saveImageDialog = new SaveFileDialog();
saveImageDialog.Title = "Select output file:";
saveImageDialog.Filter = "JPeg Image|*.jpg|Bitmap Image|*.bmp|Gif Image|*.gif";
//saveImageDialog.FileName = printFileName;
if (saveImageDialog.ShowDialog() == DialogResult.OK)
{enter code here
    // Save the screenshot to the specified path that the user has chosen
    bmpScreenshot.Save(saveImageDialog.FileName, ImageFormat.Png);
}

Thanks.

Answer 1

The problem is that the coordinates in the Bounds property are relative to its parent, but CopyFromScreen needs absolute coordinates.

Try using the PointToScreen method:

Point p = this.PointToScreen(new Point(groupBox.Bounds.X, groupBox.Bounds.Y));
gfxScreenshot.CopyFromScreen(p.X, p.Y, 0, 0, 
                 groupBox.Bounds.Size, CopyPixelOperation.SourceCopy);