多个窗口向一个消息接受窗口发送消息,这个是消息接受窗口的消息处理函数
        protected override void DefWndProc(ref System.Windows.Forms.Message m)
        {
            switch (m.Msg)
            {
                case WM_COPYDATA:
                    processMyMsg(ref m);
                    break;
                default:
                    base.DefWndProc(ref m);
                    break;
            }
        }
        private static Object thisLock = new Object();
        private void processMyMsg(ref System.Windows.Forms.Message m)
        {
           lock (thisLock)
            {
                MessageBox.Show("ok");
                MessageBox.Show("ko");
            }
        }为什么会同时弹出多个ok?