ASP.NET CORE MVC 依赖反转错误与 CRUD

Question

Today i started on dependicy inversion. Before i started implenting this i had a nice CRUD system but now i got some errors. It says "Cannot implicity convert type int to ContractLayer.UsersDto" On the image you can see my controller in the middle and i think its all fine there. The error is not that clear to me. Maybe i forgot to pass an int with the function? Maybe you guys can help me out with this.

Kind regards,

Sem

Usercollection,UserController,IUserDal

Answer 1

Both your errors are simply due to type mismatches - not dependency inversion.

The signatures of the errors are

public int DeleteUser(int id);
public int CreateUser(UserDto dto);

In both cases they return an int , but you try to build an UsersDto :

UsersDto = FactoryLayer.UserDalFactory.GetUserDal().DeleteUser(Id);

You either have to change to signature of the corresponding methods in your UserCollection or your IUsersDal to the correct type.

I'd suggest you change the Delete method to public void DeleteUser(int id); and the consuming method to:

public void Delete(int id) { ... }

When it comes to the create method I would change the signature in your IUserDal to public UsersDto Create(UsersDto dto); and then also adapt the concreate class that is implementing that interface accordingly.