WinForm-页面与Panel改圆角

#region Form圆角
        public void SetWindowRegion()
        {
            System.Drawing.Drawing2D.GraphicsPath FormPath;
            FormPath = new System.Drawing.Drawing2D.GraphicsPath();
            Rectangle rect = new Rectangle(0, 0, this.Width, this.Height - 22);
            FormPath = GetRoundedRectPath(rect, 50);
            this.Region = new Region(FormPath);
        }
        private GraphicsPath GetRoundedRectPath(Rectangle rect, int radius)
        {
            int diameter = radius;
            Rectangle arcRect = new Rectangle(rect.Location, new Size(diameter, diameter));
            GraphicsPath path = new GraphicsPath();
            // 左上角 
            path.AddArc(arcRect, 180, 90);
            // 右上角 
            arcRect.X = rect.Right - diameter;
            path.AddArc(arcRect, 270, 90);
            // 右下角 
            arcRect.Y = rect.Bottom - diameter;
            path.AddArc(arcRect, 0, 90);
            // 左下角 
            arcRect.X = rect.Left;
            path.AddArc(arcRect, 90, 90);
            path.CloseFigure();
            return path;
        }
        protected override void OnResize(System.EventArgs e)
        {
            this.Region = null;
            SetWindowRegion();
        }
#endregion