Winform鼠标左键点击按钮弹出设置菜单

        /// <summary>
        /// 鼠标左键点击按钮弹出设置菜单
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button2_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                contextMenuStrip2.Show((Button)sender, new Point(e.X, e.Y));
            }
        }