public class TaxCalculator: ICalculator, ITaxCalculator, ICanCalculate, ITransientDependency
{
}
````
``TaxCalculator`` class exposes ``ITaxCalculator`` interface with the key ``tax`` and ``ICalculator`` interface with the key ``calculator``. That means you can get keyed services from the ``IServiceProvider`` as shown below:
````C#
var taxCalculator = ServiceProvider.GetRequiredKeyedService<ITaxCalculator>("taxCalculator");
var calculator = ServiceProvider.GetRequiredKeyedService<ICalculator>("calculator");
````
> Notice that the ``ExposeKeyedServiceAttribute`` is only expose keyed services. So, you can not inject ``ITaxCalculator`` or ``ICalculator`` in your application. If you want to expose both keyed and non-keyed services, you can use ``ExposeServicesAttribute`` and ``ExposeKeyedServiceAttribute`` together as shown below:
public class TaxCalculator: ICalculator, ITaxCalculator, ICanCalculate, ITransientDependency
{
}
````
### Manually Registering
### Manually Registering
In some cases, you may need to register a service to the `IServiceCollection` manually, especially if you need to use custom factory methods or singleton instances. In that case, you can directly add services just as [Microsoft documentation](https://docs.microsoft.com/en-us/aspnet/core/fundamentals/dependency-injection) describes. Example:
In some cases, you may need to register a service to the `IServiceCollection` manually, especially if you need to use custom factory methods or singleton instances. In that case, you can directly add services just as [Microsoft documentation](https://docs.microsoft.com/en-us/aspnet/core/fundamentals/dependency-injection) describes. Example:
maliming
3 years ago