.NET 5.0+ 无需依赖第三方 原生实现定时任务

前提条件 了解异步编程

使用 async 修饰符可将方法、lambda 表达式或匿名方法指定为异步。 如果对方法或表达式使用此修饰符，则其称为异步方法 。

引用微软官方文档 https://docs.microsoft.com/zh-cn/dotnet/csharp/programming-guide/concepts/async/

业务场景适合 定时同步或推送 数据等

一、了解 BackgroundService 抽象类结构

 1 namespace Microsoft.Extensions.Hosting
 2 {
 3     //
 4     // 摘要:
 5     //     Base class for implementing a long running Microsoft.Extensions.Hosting.IHostedService.
 6     public abstract class BackgroundService : IHostedService, IDisposable
 7     {
 8         protected BackgroundService();
 9 
10         //
11         // 摘要:
12         //     Gets the Task that executes the background operation.
13         //
14         // 言论：
15         //     Will return null if the background operation hasn't started.
16         public virtual Task ExecuteTask { get; }
17 
18         public virtual void Dispose();
19         //
20         // 摘要:
21         //     Triggered when the application host is ready to start the service.
22         //
23         // 参数:
24         //   cancellationToken:
25         //     Indicates that the start process has been aborted.
26         public virtual Task StartAsync(CancellationToken cancellationToken);
27         //
28         // 摘要:
29         //     Triggered when the application host is performing a graceful shutdown.
30         //
31         // 参数:
32         //   cancellationToken:
33         //     Indicates that the shutdown process should no longer be graceful.
34         public virtual Task StopAsync(CancellationToken cancellationToken);
35         //
36         // 摘要:
37         //     This method is called when the Microsoft.Extensions.Hosting.IHostedService starts.
38         //     The implementation should return a task that represents the lifetime of the long
39         //     running operation(s) being performed.
40         //
41         // 参数:
42         //   stoppingToken:
43         //     Triggered when Microsoft.Extensions.Hosting.IHostedService.StopAsync(System.Threading.CancellationToken)
44         //     is called.
45         //
46         // 返回结果:
47         //     A System.Threading.Tasks.Task that represents the long running operations.
48         protected abstract Task ExecuteAsync(CancellationToken stoppingToken);
49     }
50 }

二、继承 BackgroundService 抽象类 实现 ExecuteAsync 执行异步方法

 1 public class CustomBackgroundService : BackgroundService
 2     {
 3         protected override async Task ExecuteAsync(CancellationToken stoppingToken)
 4         {
 5             while (!stoppingToken.IsCancellationRequested)
 6             {
 7 
 8                 //你的业务逻辑
 9                 System.Console.WriteLine($"{DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff")} 自定义定时后台服务");
10 
11                 await Task.Delay(2400);//延迟等待 毫秒为单位 
12             }
13         }
14     }

三、Program 类注入服务

1 var builder = WebApplication.CreateBuilder(args);
2 builder.Services.AddHostedService<CustomBackgroundService>();//注入服务

四、实现效果