sharepoint - 在 SharePoint 2010 的 WebApplication-Feature 中查找 JobDefinition 时出现问题

Question

我在 WebApplication-Scope 下获得了一个 SharePoint-Feature，它应该创建一个 Timer-Job。

在功能激活（在创建该作业之前）和功能取消激活时，如果该作业已经存在，我想删除它。这是功能激活代码：

public class myJob : SPJobDefinition
  public myJob() : base("JobName", SPAdministrationWebApplication.Local, null, SPJobLockType.Job) {}
}

public class JobFeature : SPFeatureReceiver
{
  public override void FeatureActivated(SPFeatureReceiverProperties properties)
  {
    SPWebApplication application = properties.Feature.Parent as SPWebApplication;
    // 1. Delete old Job if exists
    foreach (SPJobDefinition job in application.JobDefinitions)
    {
      if (string.Equals(job.Name, "JobName"))
      {
        job.Delete();   // NEVER GETS HERE
      }
    }
    // 2. Install job
    myJob deploymentJob = new myJob();
    SPMinuteSchedule schedule = new SPMinuteSchedule { BeginSecond = 0, EndSecond = 59, Interval = 5 };
    deploymentJob.Schedule = schedule;
    deploymentJob.Update(); // CRASHES
  }
}

问题是：永远不会到达应该删除作业的代码。这份工作似乎不在 application.JobDefinitions 中。（上面代码中的“// 永远不会到达这里”）

但是当我尝试创建部署作业时，我得到了一个作业已经存在的异常（上面代码中的“// CRASHES”）：

{"An object of the type myJob named \"JobName\" already exists under the parent Microsoft.SharePoint.Administration.SPAdministrationWebApplication named \"\".  Rename your object or delete the existing object."}

错误在哪里？

Answer 1

当使用另一个构造函数时，它可以工作......

public myJob(SPWebApplication application)
            : base("JobName", application, null, SPJobLockType.Job)
        {

        }