WINFORM窗体圆角+四边阴影

publicvoidSetBits(){//绘制绘图层背景Bitmapbitmap=newBitmap(Main.Width+10,Main.Height+10);Rectangle_BacklightLTRB=newRectangle(20,20,20,20);//窗体光泽重绘边界Graphicsg=Graphics.FromImage(bitmap);g.SmoothingMode=SmoothingMode.HighQuality;//高质量g.PixelOffsetMode=PixelOffsetMode.HighQ