Winform 窗体实现圆角展示

触发窗体的Resize事件，如下所示：

 #region 界面实现圆角
        private void LoginForm_Resize(object sender, EventArgs e)
        {
            if (this.WindowState == FormWindowState.Normal)
            {
                SetWindowRegion();
            }
            else
            {
                this.Region = null;
            }
        }

        public void SetWindowRegion()
        {
            System.Drawing.Drawing2D.GraphicsPath FormPath;
            FormPath = new System.Drawing.Drawing2D.GraphicsPath();
            Rectangle rect = new Rectangle(0, 0, this.Width, this.Height);
            FormPath = GetRoundedRectPath(rect, 10);//10代表圆角角度大小
            this.Region = new Region(FormPath);
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="rect">窗体大小</param>
        /// <param name="radius">圆角大小</param>
        /// <returns></returns>
        private GraphicsPath GetRoundedRectPath(Rectangle rect, int radius)
        {
            int diameter = radius;
            Rectangle arcRect = new Rectangle(rect.Location, new Size(diameter, diameter));
            GraphicsPath path = new GraphicsPath();

            path.AddArc(arcRect, 180, 90);//左上角

            arcRect.X = rect.Right - diameter;//右上角
            path.AddArc(arcRect, 270, 90);

            arcRect.Y = rect.Bottom - diameter;// 右下角
            path.AddArc(arcRect, 0, 90);

            arcRect.X = rect.Left;// 左下角
            path.AddArc(arcRect, 90, 90);
            path.CloseFigure();
            return path;
        }

        #endregion