C# 控件截图

Point screenPoint = 控件.PointToScreen(new Point());
Rectangle rect = new Rectangle(screenPoint, chartCellLine.Size);
Image img = new Bitmap(rect.Width, rect.Height);
Graphics g = Graphics.FromImage(img);
g.CopyFromScreen(rect.X - 1, rect.Y - 1, 0, 0, rect.Size);
img.Save(strPicPath, System.Drawing.Imaging.ImageFormat.Jpeg);