Unable to resolve class library references in dotnet core 5 app

Question

I have class library and i have used that class library as a project reference in my dotnet core 5 webapi project.

And i have used it in the controller like this

But when i hit this controller from post man i get error saying:

Im not sure what i am doing wrong.

Answer 1

The original error message means you did not register service with the IoC container in the startup.cs file.

services.AddScoped<IAccountService, AccountService>();

Please read the official documentation.

https://learn.microsoft.com/en-us/aspnet/core/fundamentals/dependency-injection?view=aspnetcore-5.0

Also, please post code on the forum using the "Code Sample" button rather than a screenshot

Answer 2

Hi @Muhammad Nabeel Iqbal

Your VirtualAssistantsController should be changed like below. Then the VirtualAssistantsController will be successfully initialized and the services can be injected into the Controller.

public class VirtualAssistantsController : Controller  
{  
    private readonly ILogger<VirtualAssistantsController> _logger;  
    private readonly WebUserService _webUserService;  
    private readonly AllControllerServices _services;  
    private readonly  AccountService _accountService;  
    public HomeController(ILogger<VirtualAssistantsController> logger, WebUserService webUserService, AllControllerServices services, AccountService accountService)  
    {  
        _logger = logger;  
        _webUserService = webUserService;  
        _services = services;  
        _accountService = accountService;  
    }  
    ....  
}  

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Best Regards,
Jason

Answer 3

Hello Jason thanks for writing back.
I have a controller base class on which WebUserService webUserService, AllControllerServices services are registered.

this is what library class looks like

and this is how basecontoller looks like