/// <summary>
 /// 单例模式
 /// </summary>
 /// <returns></returns>
 public static ScheduledService GetInstance()
 {
     if (self == null)
     {
         lock (l)
         {
             self = new ScheduledService();
         }
     }
     return(self);
 }
 /// <summary>
 /// 单例模式
 /// </summary>
 /// <returns></returns>
 public static ScheduledService GetInstance()
 {
     if (self==null)
     {
         lock (l)
         {
             self = new ScheduledService();
         }
     }
     return self;
 }