public FrmMain()

        {

            InitializeComponent();

            //窗体显示特效

            Opacity = 0.0; //窗体透明度为0

            fadeTimer.Start(); //计时开始

        }

        private void fadeTimer_Tick(object sender, EventArgs e)

        {

            const double d = 0.10;

            if (Opacity + d >= 1.0)

            {

                Opacity = 1.0;

                fadeTimer.Stop();

            }

            else

            {

                Opacity += d;

            }

        }