winform自定义窗体： 最大化、最小化、关闭、窗体拖动、窗体圆角、

 #region 窗体圆角的实现
        private void Form1_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);
            this.Region = new Region(FormPath);
        }

        /// 

        /// 
        /// 
        /// 窗体大小
        /// 圆角大小
        /// 
        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
        #region 窗体拖动
        Point mouseOff;
        bool leftFlag=false;
        //第一步
        private void Form1_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button==MouseButtons.Left)
            {
                mouseOff = new Point(-e.X,-e.Y);
                leftFlag = true;
            }
        }
        //第二步
        private void Form1_MouseMove(object sender, MouseEventArgs e)
        {
            if (leftFlag)
            {
                Point mouseSet = Control.MousePosition;
                mouseSet.Offset(mouseOff.X,mouseOff.Y);
                this.Location = mouseSet;
            }
        }
        //第三步
        private void Form1_MouseUp(object sender, MouseEventArgs e)
        {
            if (leftFlag)
            {
                leftFlag = false;
            }
        }
        #endregion
        #region 最小化、最大化、关闭
        private void Close_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void MaximumSize_Click(object sender, EventArgs e)
        {
            if (this.WindowState == FormWindowState.Maximized)
                this.WindowState = FormWindowState.Normal;
            else
                this.WindowState = FormWindowState.Maximized;
        }

        private void MinimumSize_Click(object sender, EventArgs e)
        {
            this.WindowState = FormWindowState.Minimized ;
        }
        #endregion