asp.net 实现定时执行 一个方法

 asp.net 实现定时执行 一个方法
public class Time_Task
{
    public event System.Timers.ElapsedEventHandler ExecuteTask;
    private static readonly Time_Task _task = null;
    private System.Timers.Timer _timer = null;
    private int _interval = 1000;
    public int Interval
    {
        set
        {
            _interval = value;
        }
        get
        {
            return _interval;
        }
    }
   
    static Time_Task()
    {
        _task = new Time_Task();
    }
   
    public static Time_Task Instance()
    {
        return _task;
    }
   
    public void Start()
    {
        if(_timer == null)
        {
            _timer = new System.Timers.Timer(_interval);
            _timer.Elapsed += new System.Timers.ElapsedEventHandler(_timer_Elapsed);
            _timer.Enabled = true;
            _timer.Start();
        }
    }
   
    protected void _timer_Elapsed(object sender, System.Timers