相关疑难解决方法(0)

我正在尝试在托管服务中使用DBContext，但收到此错误。我尝试遵循此已 接受的答案，但是以某种方式无法正常工作，我不确定自己在做什么错。

我是.net的新手，请引导我朝正确的方向发展。

未处理的异常：System.InvalidOperationException：无法使用单例“ Microsoft.AspNetCore.Hosting.Internal.HostedServiceExecutor”中的作用域服务“ StatusApp.Context.DBContext”。

public class TokenService : IHostedService
{
    public IConfiguration _Configuration { get; }
    protected IMemoryCache _cache;
    private Timer _timer;
    public IHttpClientFactory _clientFactory;
    public DBContext _DBcontext;

    private readonly IServiceScopeFactory _scopeFactory;

    public TokenService(IConfiguration configuration, IMemoryCache memoryCache, IHttpClientFactory clientFactory, DBContext DBcontext, IServiceScopeFactory scopeFactory)
    {
        _Configuration = configuration;
        _cache = memoryCache;
        _clientFactory = clientFactory;
        _scopeFactory = scopeFactory;
        _DBcontext = _scopeFactory.CreateScope().ServiceProvider.GetRequiredService<DBcontext>();
    }

    public Task StartAsync(CancellationToken cancellationToken)
    {
        _timer = new Timer(getOrg, null, 0, 1000);
        return Task.CompletedTask;
    }

    public Task …