No service for type ‘mediatr.irequesthandler

Solution for query – no service for type ‘mediatr.irequesthandler’

The error message “no service for type ‘mediatr.irequesthandler'” usually occurs when the application is unable to find the required service implementation for the specified type. This error commonly arises in dependency injection scenarios, where the application is trying to inject an instance of a specific type into a class or component but is unable to locate a suitable implementation of that type.

To resolve this issue, you need to ensure that you have registered the required service and its corresponding implementation correctly within your application’s dependency injection container, such as the ASP.NET Core DI container.

Example:

Let’s consider an example where you have defined an interface called IRequestHandler and you are trying to inject its implementation into a UserController class:

      
      public interface IRequestHandler
      {
         void HandleRequest();
      }

      public class RequestHandler : IRequestHandler
      {
         public void HandleRequest()
         {
            // Implementation code here
         }
      }

      public class UserController
      {
         private readonly IRequestHandler _requestHandler;

         public UserController(IRequestHandler requestHandler)
         {
            _requestHandler = requestHandler;
         }

         // Other methods and properties
      }
      
   

In the example above, if you encounter the “no service for type ‘mediatr.irequesthandler'” error, it means that you have not registered the RequestHandler implementation of IRequestHandler in your DI container.

In ASP.NET Core, you can register the service and its implementation in the ConfigureServices method of your Startup class as follows:

      
      public void ConfigureServices(IServiceCollection services)
      {
         // Other services and configurations

         services.AddTransient();
      }
      
   

This will register the RequestHandler implementation for the IRequestHandler interface and enable the DI container to resolve the dependency correctly when injecting it into the UserController class.