C#画圆角矩形的方法

protected void Page_Load(object sender, EventArgs e){ Bitmap bm = new Bitmap(800, 600); Graphics g = Graphics.FromImage(bm); g.FillRectangle(Brushes.White,new Rectangle(0,0,800,600)); FillRoundRectangle(g,Brushes.Plum,new Rectangle(100, 100, 100, 100), 8); DrawRoundRectangle(g, Pens.Yellow,new Rectangle(100, 100, 100, 100), 8); bm.Save(Response.OutputStream, ImageFormat.Jpeg); g.Dispose(); bm.Dispose();}public static void DrawRoundRectangle(Graphics g,Pen pen,Rectangle rect, int cornerRadius){ using (GraphicsPath path = CreateRoundedRectanglePath(rect, cornerRadius)) {  g.DrawPath(pen, path); }}public static void FillRoundRectangle(Graphics g, Brush brush,Rectangle rect, int cornerRadius){ using (GraphicsPath path = CreateRoundedRectanglePath(rect, cornerRadius)) {  g.FillPath(brush, path); }}internal static GraphicsPath CreateRoundedRectanglePath(Rectangle rect, int cornerRadius){ GraphicsPath roundedRect = new GraphicsPath(); roundedRect.AddArc(rect.X, rect.Y, cornerRadius * 2, cornerRadius * 2, 180, 90); roundedRect.AddLine(rect.X + cornerRadius, rect.Y, rect.Right - cornerRadius * 2, rect.Y); roundedRect.AddArc(rect.X + rect.Width - cornerRadius * 2, rect.Y, cornerRadius * 2, cornerRadius * 2, 270, 90); roundedRect.AddLine(rect.Right, rect.Y + cornerRadius * 2, rect.Right, rect.Y + rect.Height - cornerRadius * 2); roundedRect.AddArc(rect.X + rect.Width - cornerRadius * 2, rect.Y + rect.Height - cornerRadius * 2, cornerRadius * 2, cornerRadius * 2, 0, 90); roundedRect.AddLine(rect.Right - cornerRadius * 2, rect.Bottom, rect.X + cornerRadius * 2, rect.Bottom); roundedRect.AddArc(rect.X, rect.Bottom - cornerRadius * 2, cornerRadius * 2, cornerRadius * 2, 90, 90); roundedRect.AddLine(rect.X, rect.Bottom - cornerRadius * 2, rect.X, rect.Y + cornerRadius * 2); roundedRect.CloseFigure(); return roundedRect;}