Question

c#如何将panel中画的图以图片保存？ Graphics g = mypanel.CreateGraphics();

panel.Save(OpenFileDialog1.FileName);提示 未将对象实例化
采用 Bitmap bt = new Bitmap(mypanel.Width,mypanel.Height);
Graphics g = Graphics.FromImage(bt);
这种形式到可以保存。
但我每次要调用画图类累加画图，请问如何保存panel

Answer 1

Bitmap bt = new Bitmap(mypanel.Width,mypanel.Height);
mypanel.tobitmap(bt);
bt.Save(OpenFileDialog1.FileName);

Answer 2

bt.Save("test.jpg",ImageFormart.Jpeg);

System.Drawing.Imaging.ImageFormat