C#定时器的使用

timer timer1;
        this.timer1.interval = 1000;
        this.timer1.tick += new system.eventhandler(this.timer1_tick);

        private void timer1_tick(object sender, eventargs e)
        {
            arraylist autotask = new arraylist();           
            autotask.add("8:30:00");
            autotask.add("9:30:00");
            autotask.add("10:30:00");
            autotask.add("11:30:00");

            for (int n = 0; n < 4; n++)
            {
                if (dtauto.tolongtimestring().equals(autotask[n]))
                {
                    messagebox.show("现在时间是" + autotask[n]);
                }
            }
        }