无边框窗体的移动以及全屏代码

#region //窗体移动与放大
        System.Drawing.Point mouseOff;//鼠标移动位置变量
        bool leftFlag;//标签是否为左键

        private void Form_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                mouseOff = new System.Drawing.Point(-e.X, -e.Y); //得到变量的值
                leftFlag = true;                  //点击左键按下时标注为true;
            }
        }

        private void Form_MouseMove(object sender, MouseEventArgs e)
        {
            if (leftFlag)
            {
                System.Drawing.Point mouseSet = Control.MousePosition;
                mouseSet.Offset(mouseOff.X, mouseOff.Y);  //设置移动后的位置
                this.Location = mouseSet;
            }
        }

        private void Form_MouseUp(object sender, MouseEventArgs e)
        {
            if (leftFlag)
            {
                leftFlag = false;//释放鼠标后标注为false;
            }
        }

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