private ITask CreateTask(ILifetimeScope scope)

         {

             ITask task = null;

             if (this.Enabled)

             {

                 var type2 = System.Type.GetType(this.Type);

                 if (type2 != null)

                 {

                     object instance;

                     if (!EngineContext.Current.ContainerManager.TryResolve(type2, scope, out instance))

                     {

                         //not resolved

                         instance = EngineContext.Current.ContainerManager.ResolveUnregistered(type2, scope);

                     }

                     task = instance as ITask;

                 }

             }

             return task;

         }

         /// <summary>

         /// Executes the task

         /// </summary>

         /// <param name="throwException">A value indicating whether exception should be thrown if some error happens</param>

         /// <param name="dispose">A value indicating whether all instances should be disposed after task run</param>

         /// <param name="ensureRunOnOneWebFarmInstance">A value indicating whether we should ensure this task is run on one farm node at a time</param>

         public void Execute(bool throwException = false, bool dispose = true, bool ensureRunOnOneWebFarmInstance = true)

         {

             ...

                 //initialize and execute 初始化成功后执行任务

                 var task = this.CreateTask(scope);

                 if (task != null)

                 {

                     this.LastStartUtc = DateTime.UtcNow;

                     if (scheduleTask != null)

                     {

                         //update appropriate datetime properties

                         scheduleTask.LastStartUtc = this.LastStartUtc;

                         scheduleTaskService.UpdateTask(scheduleTask);

                     }

                     task.Execute();

                     this.LastEndUtc = this.LastSuccessUtc = DateTime.UtcNow;

                 }

             }

             catch (Exception exc)

             {

                 this.Enabled = !this.StopOnError;

                 this.LastEndUtc = DateTime.UtcNow;

                 //log error

                 var logger = EngineContext.Current.ContainerManager.Resolve<ILogger>("", scope);

                 logger.Error(string.Format("Error while running the '{0}' schedule task. {1}", this.Name, exc.Message), exc);

                 if (throwException)

                     throw;

             }

             if (scheduleTask != null)

             {

                 //update appropriate datetime properties

                 scheduleTask.LastEndUtc = this.LastEndUtc;

                 scheduleTask.LastSuccessUtc = this.LastSuccessUtc;

                 scheduleTaskService.UpdateTask(scheduleTask);

             }

             //dispose all resources

             if (dispose)

             {

                 scope.Dispose();

             }

         }