但是对于我们的MyServiceProvider对象来说，当调用它的GetService方法试图获取ServiceScopeFactory对象的时候，获取的实际上是被封装的那个SerivceProvider关联的ServiceScopeFactory，那么很自然创建的“子ServiceProvider”也与MyServiceProvider没有什么关系。
三、如何解决这个问题？
既然我们知道了问题的根源，我们自然就有了解决方案。解决方案并不复杂，我们只需要MyServiceProvider的GetService方法返回反映其自身服务注册相关的ServiceScopeFactory。为此我们定义了如下一个ServiceScope和对应的ServiceScopeFactory。
internal class ServiceScope : IServiceScope { private MyServiceProvider _serviceProvider; public ServiceScope(IServiceScope innserServiceScope, Dictionary<Type, Type> services) { _serviceProvider = new MyServiceProvider(innserServiceScope.ServiceProvider, services); } public IServiceProvider ServiceProvider { get { return _serviceProvider; } } public void Dispose() { _serviceProvider.Dispose(); } } internal class ServiceScopeFactory : IServiceScopeFactory { private IServiceScopeFactory _innerServiceFactory; private Dictionary<Type, Type> _services; public ServiceScopeFactory(IServiceScopeFactory innerServiceFactory, Dictionary<Type, Type> services) { _innerServiceFactory = innerServiceFactory; _services = services; } public IServiceScope CreateScope() { return new ServiceScope(_innerServiceFactory.CreateScope(), _services); } }
除此之外，我们为MyServiceProvider添加了一个构造函数，GetService方法也针对IServiceScopeFactory添加了相应的代码。
public class MyServiceProvider : IServiceProvider, IDisposable { public MyServiceProvider(IServiceProvider innerServiceProvider, Dictionary<Type, Type> services) { _innerServiceProvider = innerServiceProvider; _services = services; _disposables = new List<IDisposable>(); } public object GetService(Type serviceType) { if (serviceType == typeof(IServiceScopeFactory)) { IServiceScopeFactory innerServiceScopeFactory = _innerServiceProvider.GetRequiredService<IServiceScopeFactory>(); return new ServiceScopeFactory(innerServiceScopeFactory, _services); } ... } ... }
以上分享，希望能对需要解决这样问题的朋友有所帮助！
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