.netCore 使用Quartz做定时任务

参考：https://www.cnblogs.com/LinWenQiang/p/13460283.html

Quartz 由三个部分组成，分别为Schedule（调度器）、Trigger（触发器）、JobDetail（任务）

1、首先在项目中添加Quartz  nuget 包。

2、创建我们的任务，在项目中添加MyJob,并继承接口Ijob 

[DisallowConcurrentExecution]
public class MyJob : IJob
{
    private readonly ILogger<MyJob> _logger;
    public MyJob(ILogger<MyJob> logger)
    {
         _logger = logger;
    }

    public Task Execute(IJobExecutionContext context)
    {
        _logger.LogInformation("MyJob start");
        //在此处编写任务业务代码
        return Task.CompletedTask;
    }
}

DisallowConcurrentExecution：防止运行多个相同的实例

 3、创建调度类JobSchedule

public class JobSchedule
    {
        public JobSchedule(Type jobType, string cronExpression)
        {
            this.JobType = jobType ?? throw new ArgumentNullException(nameof(jobType));
            CronExpression = cronExpression ?? throw new ArgumentNullException(nameof(cronExpression));
        }
        /// <summary>
        /// Job类型
        /// </summary>
        public Type JobType { get; private set; }
        /// <summary>
        /// Cron表达式
        /// </summary>
        public string CronExpression { get; private set; }
        /// <summary>
        /// Job状态
        /// </summary>
        public JobStatus JobStatu { get; set; } = JobStatus.Init;
    }
    /// <summary>
    /// Job运行状态
    /// </summary>
    public enum JobStatus : byte
    {
        [Description("初始化")]
        Init = 0,
        [Description("运行中")]
        Running = 1,
        [Description("调度中")]
        Scheduling = 2,
        [Description("已停止")]
        Stopped = 3,
    }

 4、添加调度工厂SingletonJobFactory

public class SingletonJobFactory: IJobFactory
    {
        private readonly IServiceScope _serviceScope;
        public SingletonJobFactory(IServiceProvider serviceProvider)
        {
            _serviceScope = serviceProvider.CreateScope();
        }

        public IJob NewJob(TriggerFiredBundle bundle, IScheduler scheduler)
        {
            return _serviceScope.ServiceProvider.GetRequiredService(bundle.JobDetail.JobType) as IJob;
        }

        public void ReturnJob(IJob job)
        {
            (job as IDisposable)?.Dispose();
        }
    }

5、创建QuartzHostedService类，并继承 IHostedService

    public class QuartzHostedService : IHostedService
    {
        private readonly IJobFactory _jobFactory;
        private readonly IEnumerable<JobSchedule> _jobSchedules;

        public QuartzHostedService(IJobFactory jobFactory,
            IEnumerable<JobSchedule> jobSchedules)
        {
            _jobSchedules = jobSchedules;
            _jobFactory = jobFactory;
        }
        public IScheduler Scheduler { get; set; }

        public async Task StartAsync(CancellationToken cancellationToken)
        {
            Scheduler = await StdSchedulerFactory.GetDefaultScheduler(cancellationToken);
            Scheduler.JobFactory = _jobFactory;

            foreach (var jobSchedule in _jobSchedules)
            {
                var job = CreateJob(jobSchedule);
                var trigger = CreateTrigger(jobSchedule);

                await Scheduler.ScheduleJob(job, trigger, cancellationToken);
            }

            await Scheduler.Start(cancellationToken);
        }

        public async Task StopAsync(CancellationToken cancellationToken)
        {
            await Scheduler?.Shutdown(cancellationToken);
        }

        private static IJobDetail CreateJob(JobSchedule schedule)
        {
            var jobType = schedule.JobType;
            return JobBuilder
                .Create(jobType)
                .WithIdentity(jobType.FullName)
                .WithDescription(jobType.Name)
                .Build();
        }

        private static ITrigger CreateTrigger(JobSchedule schedule)
        {
            return TriggerBuilder
                .Create()
                .WithIdentity($"{schedule.JobType.FullName}.trigger")
                .WithCronSchedule(schedule.CronExpression)
                .WithDescription(schedule.CronExpression)
                .Build();
        }
    }

6、在Startup进行注册

public void ConfigureServices(IServiceCollection services)
        {
            
            //添加Quartz服务
            services.AddSingleton<IJobFactory, SingletonJobFactory>();
            services.AddSingleton<ISchedulerFactory, StdSchedulerFactory>();
            //添加我们的Job
            services.AddScoped<MyJob>();//这里注册时有个坑，一定要注意
            services.AddSingleton(
                 new JobSchedule(jobType: typeof(MyJob), cronExpression: Configuration["TimingTask"])
           );
            // ...         
        }

定时时间我这里写到appsettings.json配置文件中了，方便更改：

"TimingTask": "0 45 10 * * ?",

关于Cron表达式，可以看官方文档：

https://www.quartz-scheduler.net/documentation/quartz-3.x/tutorial/crontrigger.html#examples