C#禁用右上角x关闭按钮

        /// <summary>
        /// 禁用x
        /// </summary>
        /// <param name="m"></param>
        protected override void WndProc(ref Message m)
        {
            if (m.Msg == 0x0112 && (int)m.WParam == 0xF060)
            {
                return;
            }
            base.WndProc(ref m);
        }