How to get bitmap from painted panel in C#
问题 I have a panel and I use it's Graphics gr = panel1.CreateGraphics() to draw lines and other stuff. I need to get pixel color of the point where mouse is clicked, so I decided to use GetPixel method of Bitmap. I create bitmap this way: Bitmap b = new Bitmap(width, height); panel1.DrawToBitmap(b, new Rectangle(0, 0, width, height)); b.Save("D:/aaa.bmp"); but I get only white rectangle even if I've drawn anything. What's the problem? 回答1: Only things that are drawn in the Paint event will be