1、Graphics.FillRectangle()方法.2、 Bitmap bmp=new Bitmap();
panel1.BackgroundImage=(Image) bmp; Graphics g=Graphics.FromImage(panel1.BackgroundImage);
//保存
g.Save(@"e:\123.bmp");
panel1.BackgroundImage=(Image) bmp; Graphics g=Graphics.FromImage(panel1.BackgroundImage);
//保存
g.Save(@"e:\123.bmp");
panel1.BackgroundImage.Save(@"e:\123.bmp");