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我正在构建一个 ASP.NET Web API (.NET 5)。除了拥有典型的控制器之外，我还希望有一个始终并行运行的后台作业。为此，我创建了一个托管服务：

public class MyHostedService : IHostedService
{
    private readonly IHostApplicationLifetime _appLifetime;
    private readonly ILogger _logger;

    public MyHostedService(IHostApplicationLifetime appLifetime, ILogger<MyHostedService> logger)
    {
        _appLifetime = appLifetime ?? throw new ArgumentNullException(nameof(appLifetime));
        _logger = logger ?? throw new ArgumentNullException(nameof(logger));
    }

    public Task StartAsync(CancellationToken cancellationToken)
    {             
        return Task.Factory.StartNew(async () =>
        {
            await Run(cancellationToken);
        }, cancellationToken, TaskCreationOptions.LongRunning, TaskScheduler.Default);
    }

    private async Task Run(CancellationToken cancellationToken)
    {
        try
        {
            // some long running code
        }
        catch (OperationCanceledException)
        {
            _logger.LogInformation("Application was terminated from the outside");
            _appLifetime.StopApplication();
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Unhandled exception!");
            _appLifetime.StopApplication();
        }
    }

    public Task StopAsync(CancellationToken cancellationToken)
    {
        _logger.LogDebug("StopAsync executes");
        return Task.CompletedTask;
    }
}

我注册了它ConfigureServices：

public void ConfigureServices(IServiceCollection services)
{
  services.AddControllers();
  services.AddSwaggerGen(c =>
  {
      c.SwaggerDoc("v1", new OpenApiInfo {Title = "My API", Version = "v1"});
  });

  services.AddHostedService<CacheManagerHostedService>();
}

API 工作正常，MyHostedService实例运行正常。中的代码StartAsync启动了一个新线程。如果我不这样做，API 服务器根本不会开始监听。我注意到当我按下 CTRL+C 时应用程序几乎立即关闭。StopAsync永远不会写入日志。我希望以后能够进行一些清理StopAsync。我应该改变什么？

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0 回答 0