Bitmap bit = new Bitmap(pictureBox1.Width, pictureBox1.Height);
pictureBox1.DrawToBitmap(bit, pictureBox1.ClientRectangle);
bit.Save("D:\Picture1.bmp", System.Drawing.Imaging.ImageFormat.Bmp);
bit.Dispose();
为什么在Picture1.bmp中只显示在pictureBox1_Paint中画的图,而没有现在我在另一个里面添加的线