Winform圆角窗体绘制

将Winform窗体改为圆角的：

方法一：

 private void FormLogin_Paint(object sender, PaintEventArgs e)
        {
            //圆角窗体
           orm form = ((Form)sender);
            List<Point> list = new List<Point>();
            int width = form.Width;
            int height = form.Height;

            //左上
           list.Add(new Point(0, 5));
            list.Add(new Point(1, 5));
            list.Add(new Point(1, 3));
            list.Add(new Point(2, 3));
            list.Add(new Point(2, 2));
            list.Add(new Point(3, 2));
            list.Add(new Point(3, 1));
            list.Add(new Point(5, 1));
            list.Add(new Point(5, 0));

            //右上
           list.Add(new Point(width - 5, 0));
            list.Add(new Point(width - 5, 1));
            list.Add(new Point(width - 3, 1));
            list.Add(new Point(width - 3, 2));
            list.Add(new Point(width - 2, 2));
            list.Add(new Point(width - 2, 3));
            list.Add(new Point(width - 1, 3));
            list.Add(new Point(width - 1, 5));
            list.Add(new Point(width - 0, 5));
            //右下
          list.Add(new Point(width - 0, height - 5));
            list.Add(new Point(width - 1, height - 5));
            list.Add(new Point(width - 1, height - 3));
            list.Add(new Point(width - 2, height - 3));
            list.Add(new Point(width - 2, height - 2));
            list.Add(new Point(width - 3, height - 2));
            list.Add(new Point(width - 3, height - 1));
            list.Add(new Point(width - 5, height - 1));
            list.Add(new Point(width - 5, height - 0));
            //左下
         list.Add(new Point(5, height - 0));
            list.Add(new Point(5, height - 1));
            list.Add(new Point(3, height - 1));
            list.Add(new Point(3, height - 2));
            list.Add(new Point(2, height - 2));
            list.Add(new Point(2, height - 3));
            list.Add(new Point(1, height - 3));
            list.Add(new Point(1, height - 5));
            list.Add(new Point(0, height - 5));

            Point[] points = list.ToArray();

            GraphicsPath shape = new GraphicsPath();
            shape.AddPolygon(points);

            //将窗体的显示区域设为GraphicsPath的实例 
           form.Region = new System.Drawing.Region(shape);

        }

需要将formborderstyle设置为None；之前试过了次方法，但是界面会一直不停的闪烁，检查了下也不知道是什么原因造成的（但是有时候是可以的）。所以就使用了下面的第二种方法。此方法是完全没有问题的。

方法二：

public void SetWindowRegion()
        {
            System.Drawing.Drawing2D.GraphicsPath FormPath;
            FormPath = new System.Drawing.Drawing2D.GraphicsPath();
            Rectangle rect = new Rectangle(0, 22, this.Width, this.Height - 22);//this.Left-10,this.Top-10,this.Width-10,this.Height-10);                 
            FormPath = GetRoundedRectPath(rect, 30);
            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();
        }