How to register a service having multiple interfaces and use that service as a single instance in ConfigureServices .Net Core 3.1

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I have service which implements multiple Interfaces; for example

ServiceClass : IService1, IService2
{
// implementation
}

Now I need to register this service in ConfigureServices() in such a way that I have a single instance of SerivceClass and this instance can be used even if the IService1 or IService2 is injected via constructor. For ex,

public class SomeClass1: ISomeClass1
    {
      SomeClass1(IService1 service)
          {
           ...
          }
    }

public class SomeClass2 : SomeClass2
    {
      SomeClass2(IService2 service)
          {
           ...
          }
    }

I have tried registering the ServiceClass using its both Interfaces in ConfigureServices() but it would create multiple instances.

ConfigureServices(){

...
services.AddSingleton<IService1, ServiceClass>();
services.AddSingleton<IService2, ServiceClass>();
services.AddSingleton<ISomeClass1>(
                x => new SomeClass1(
                    x.GetRequiredService<IService1>(),
                    ));

services.AddSingleton<ISomeClass2>(
                x => new SomeClass2(
                    x.GetRequiredService<IService2>(),
                    )); 
....
}

I need to find a solution where I can inject the same instance to SomeClass1 and SomeClass2 eventhough the injected interfaces are different.

asp.net-core c#
1 Answers

One way to solve this is to register the implementing class, and then explicitly resolve the multiple interfaces from that:

services.AddSingleton<ServiceClass>();
services.AddSingleton<IService1, ServiceClass>(x => x.GetRequiredService<ServiceClass>());
services.AddSingleton<IService2, ServiceClass>(x => x.GetRequiredService<ServiceClass>());

There's an example of this approach used here for HttpClientFactory for example.

user_10641690
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