学步园

很多应用程序都需要在指定的时间(每年,每月,每周,每天,每小时)自动在后台重复执行某个流程,一般为批量处理一些记录,执行比较长的操作等.在SharePoint2013/2010中，Timer
Jobs负责host这些重复执行的流程，以及他们的排程(Schedule),本文将以SharePoint2013为例介绍如何使用TimerJobs，但是90%的步骤和概念是和SharePoint2010中一致的。

可以在管理中心查看Timer Jobs（系统自带有很多Timer Jobs）：

SharePoint Timer Service
负责执行了调度所有的 TimerJob，因此你需要确保运行该服务的账号有访问TimerJob里面需要用到的资源的权限。

下面介绍如何在SharePoint 2013：

1. 创建一个Empty的SharePoint solution(Farm) ,并建立如下代码结构

MyTimerJob.cs 负责定义 SPJobDefinition：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;

namespace TestTimerJob
{
    // 首先是要自定义一个类，继承自 SPJobDefinition
    public class MyTimerJob : SPJobDefinition
    {
        // 该构造只用于序列化和反列化，因为timer job的Definition 初始化后成为instance需要保存在数据库中
        public MyTimerJob()
            : base()
        {

        }

        // 创建针对SPService application的timer job 是调用的构造
        public MyTimerJob(string jobName, SPService service, SPServer server, SPJobLockType lockType)
            : base(jobName, service, server, lockType)
        {
            this.Title = "Products Timer Job";
        }

        // 创建针对web application的timer job 是调用的构造
        public MyTimerJob(string jobName, SPWebApplication webapp)
            : base(jobName, webapp, null, SPJobLockType.ContentDatabase)
        {
            this.Title = "Products Timer Job";
        }

        // 每次执行到Timer Job时要执行的方法。跟据Timer Job 的Schedule
        public override void Execute(Guid targetInstanceId)
        {
            SPWebApplication webapp = this.Parent as SPWebApplication;
            SPContentDatabase contentDb = webapp.ContentDatabases[targetInstanceId];

            // 取参数，通过Properties可以从外部传递参数，但要求参数可以被序列化和反列化
            string siteUrl = this.Properties["SiteUrl"].ToString();
            using (SPSite site = new SPSite(siteUrl))
            {
                // 这里可写自己的逻辑  
            }

            // 这里可写自己的逻辑 
        }      
    }
}

MyTimerJob Feature.EventReceiver.cs 负责实例化SPJobDefinition,设置排程(schedule),传递参数：

using System;
using System.Runtime.InteropServices;
using System.Security.Permissions;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;

namespace TestTimerJob.Features.MyTimerJob_Feature{

    [Guid("d3209596-8612-4891-bf08-dc0fa0f0cb98")]
    public class MyTimerJob_FeatureEventReceiver : SPFeatureReceiver
    {
        const string JobName = "My Timer Job";

        public override void FeatureActivated(SPFeatureReceiverProperties properties)
        {
            // 注意此处as 后面是SPSite还是SPWeb, SPFarm ...要根据Feature 的Scope
            SPSite site = properties.Feature.Parent as SPSite;
            
            DeleteJob(site); // Delete Job if already Exists

            CreateJob(site); // Create new Job
        }

        private static void DeleteJob(SPSite site)
        {
            foreach (SPJobDefinition job in site.WebApplication.JobDefinitions)
                if (job.Name == JobName)
                    job.Delete();
        }

        private static void CreateJob(SPSite site)        {

            // 初始化 SPJobDefinition
            MyTimerJob job = new MyTimerJob(JobName, site.WebApplication);

            // 传递参数
            job.Properties.Add("SiteUrl", site.Url);

            // 设置 schedule, 可选 SPDailySchedule, SPWeeklySchedule, SPYearlySchedule,SPMonthlyByDaySchedule，SPHourlySchedule，SPMinuteSchedule          
                
            SPMinuteSchedule schedule = new SPMinuteSchedule();
            schedule.BeginSecond = 0;
            schedule.EndSecond = 5;
            schedule.Interval = 5;

            job.Schedule = schedule;
            job.Update();

        }

        public override void FeatureDeactivating(SPFeatureReceiverProperties properties)
        {
            // 删除 Timer Job的实例
            DeleteJob(properties.Feature.Parent as SPSite); // Delete the Job
        }
    }
}