如何在一天中的特定时间运行 .net Core IHosted 服务？

Question

我在 .Net 核心 Ihosted 服务中有以下定时器运行，

TimeSpan ScheduledTimespan;
string[] formats = { @"hh\:mm\:ss", "hh\:mm" };
string strTime = Startup.Configuration["AppSettings:JobStartTime"].ToString();
var success = TimeSpan.TryParseExact(strTime, formats, CultureInfo.InvariantCulture, out ScheduledTimespan);
Timer _timer = new Timer(JobToRun, null, TimeSpan.Zero, ScheduledTimespan);

我正在使用这个特定的重载，

public Timer(TimerCallback callback, object state, TimeSpan dueTime, TimeSpan period);

但是 JobToRun 在控件到达它时立即执行。如何在每天的特定时间达到运行？提前致谢。

Answer 1

以下函数returns解析作业运行时间

private static TimeSpan getScheduledParsedTime()
{
     string[] formats = { @"hh\:mm\:ss", "hh\:mm" };
     string jobStartTime = "07:10";
     TimeSpan.TryParseExact(jobStartTime, formats, CultureInfo.InvariantCulture, out TimeSpan ScheduledTimespan);
     return ScheduledTimespan;
}

跟随函数returns 从当天当前时间开始的延迟时间。如果一天中的当前时间超过作业运行时间，适当的延迟将被添加到作业运行中，如下所示，

private static TimeSpan getJobRunDelay()
{
    TimeSpan scheduledParsedTime = getScheduledParsedTime();
    TimeSpan curentTimeOftheDay = TimeSpan.Parse(DateTime.Now.TimeOfDay.ToString("hh\:mm"));
    TimeSpan delayTime = scheduledParsedTime >= curentTimeOftheDay
        ? scheduledParsedTime - curentTimeOftheDay
        : new TimeSpan(24, 0, 0) - curentTimeOftheDay + scheduledParsedTime;
    return delayTime;
}

下面的计时器会根据JobRunDelay每天

调用methodToExecute

_timer = new Timer(methodToExecute, null, getJobRunDelay(), new TimeSpan(24, 0, 0));

Answer 2

使用 Cron 作业

创建一个 ASP.NET 核心 Web 项目
添加 NuGet 包Microsoft.Extensions.Hosting
添加 NuGet 包 Cronos

Crete Abstract class CronJobService - 在这个 CronJobService 中，我们使用一个计时器来跟踪时间并在时间达到计划时触发后台任务

public abstract class CronJobService : IHostedService, IDisposable
{
  private System.Timers.Timer _timer;
  private readonly CronExpression _expression;
  private readonly TimeZoneInfo _timeZoneInfo;

  protected CronJobService(string cronExpression, TimeZoneInfo timeZoneInfo)
  {
    _expression = CronExpression.Parse(cronExpression);
    _timeZoneInfo = timeZoneInfo;
  }

  public virtual async Task StartAsync(CancellationToken cancellationToken)
  {
   await ScheduleJob(cancellationToken);
  }

  protected virtual async Task ScheduleJob(CancellationToken cancellationToken)
  {
     var next = _expression.GetNextOccurrence(DateTimeOffset.Now, _timeZoneInfo);
     if (next.HasValue)
     {
       var delay = next.Value - DateTimeOffset.Now;
       if (delay.TotalMilliseconds <= 0)   // prevent non-positive values from being passed into Timer
       {
          await ScheduleJob(cancellationToken);
       }
       _timer = new System.Timers.Timer(delay.TotalMilliseconds);
       _timer.Elapsed += async (sender, args) =>
       {
          _timer.Dispose();  // reset and dispose timer
          _timer = null;

          if (!cancellationToken.IsCancellationRequested)
          {
              await DoWork(cancellationToken);
          }

          if (!cancellationToken.IsCancellationRequested)
          {
              await ScheduleJob(cancellationToken);    // reschedule next
          }
       };
       _timer.Start();
     }
     await Task.CompletedTask;
  }

  public virtual async Task DoWork(CancellationToken cancellationToken)
  {
     await Task.Delay(5000, cancellationToken);  // do the work
  }

  public virtual async Task StopAsync(CancellationToken cancellationToken)
  {
    _timer?.Stop();
    await Task.CompletedTask;
  }

  public virtual void Dispose()
  {
    _timer?.Dispose();
  }
}

继承自 CronJobService

  public class XXXCronJob:CronJobService
  {
    private readonly ILogger<CronJob> _logger;

    public XXXCronJob(IScheduleConfig<CronJob > config, ILogger<CronJob> logger)
    : base(config.CronExpression, config.TimeZoneInfo)
    {
     _logger = logger;
    }

    public override Task StartAsync(CancellationToken cancellationToken)
    {
     _logger.LogInformation("CronJob  starts.");
     return base.StartAsync(cancellationToken);
    }

    public override Task DoWork(CancellationToken cancellationToken)
    {
     _logger.LogInformation($"{DateTime.Now:hh:mm:ss} CronJob  is working.");
     return Task.CompletedTask;
    }

    public override Task StopAsync(CancellationToken cancellationToken)
    {
     _logger.LogInformation("CronJob  is stopping.");
     return base.StopAsync(cancellationToken);
    }
 }

添加新接口 IScheduleConfig

 public interface IScheduleConfig<T>
 {
   string CronExpression { get; set; }
   TimeZoneInfo TimeZoneInfo { get; set; }
 }

实施 IScheduleConfig

 public class ScheduleConfig<T> : IScheduleConfig<T>
 {
   public string CronExpression { get; set; }
   public TimeZoneInfo TimeZoneInfo { get; set; }
 }

添加扩展class ScheduledServiceExtensions

 public static class ScheduledServiceExtensions
 {
    public static IServiceCollection AddCronJob<T>(this IServiceCollection services, Action<IScheduleConfig<T>> options) where T : CronJobService
    {
       if (options == null)
       {
          throw new ArgumentNullException(nameof(options), @"Please provide Schedule Configurations.");
       }
       var config = new ScheduleConfig<T>();
       options.Invoke(config);
       if (string.IsNullOrWhiteSpace(config.CronExpression))
       {
          throw new ArgumentNullException(nameof(ScheduleConfig<T>.CronExpression), @"Empty Cron Expression is not allowed.");
       }

       services.AddSingleton<IScheduleConfig<T>>(config);
       services.AddHostedService<T>();
      return services;
    }
 }

使用泛型安排多个 Cron 作业

 public void ConfigureServices(IServiceCollection services)
 {
   services.AddCronJob<XXXCronJob>(c =>
   {
     c.TimeZoneInfo = TimeZoneInfo.Local;
     c.CronExpression = @"00 05 * * *";
   });
   services.AddCronJob<YYYCronJob>(c =>
   {
     c.TimeZoneInfo = TimeZoneInfo.Local;
     c.CronExpression = @"00 08 * * *";
   });
   services.AddCronJob<ZZZCronJob>(c =>
   {
     c.TimeZoneInfo = TimeZoneInfo.Local;
     c.CronExpression = @"30 14 * * *";
   });
 }

第一个是 05:00 上午。

第二个是 08:00 AM

最后一个是 14:30 下午。

如何在一天中的特定时间运行 .net Core IHosted 服务？

How to run .net Core IHosted Service at specific time Of the day?

c#

timer

.net-core

asp.net-core-hosted-services

如何在一天中的特定时间 运行 .net Core IHosted 服务？

How to run .net Core IHosted Service at specific time Of the day?

c#

timer

.net-core

asp.net-core-hosted-services

如何在一天中的特定时间运行 .net Core IHosted 服务？