Generic function correct usage?

I'm new this site, I have a repository pattern, if you check below code, here the return type & parameter T is defined which will implemented by calling methods so at run time it will be replaced by SomeClass and the parameter will be changed like it will be string, int or bool, however below will not compile however I need to make it work please help and alternative will work too.

SomeClass

public interface IBaseRepository

Task<T> Add<T>(T value,string typeName);


public class Test: IBaseRepository

public Task<SomeClass> Add<SomeClass>(string value, string typeName)

throw new NotImplementedException();


public Task<SomeClass> Add<SomeClass>(int value, string typeName)

throw new NotImplementedException();


public Task<SomeClass> Add<SomeClass>(bool value, string typeName)

throw new NotImplementedException();




Redundant Approach:

public interface IBaseRepository

Task<T> AddData<T>(string namespaceName,string typeName);

Task<T> AddData<T>(int namespaceName, string typeName);


public abstract class BaseRepo : IBaseRepository

public async Task<T> AddData<T>(string namespaceName, string typeName)

return JsonConvert.DeserializeObject<T>(namespaceName.ToString());


public async Task<T> AddData<T>(int namespaceName, string typeName)

return JsonConvert.DeserializeObject<T>(namespaceName.ToString());



public class Testing : BaseRepo

public async Task<Testing> Add(string namespaceName, string typeName)

return await AddData<Testing>(namespaceName,"");


public async Task<Testing> Add1(int namespaceName, string typeName)

return await AddData<Testing>(namespaceName, "");




3 Answers
3

public interface IBaseRepository<E>

Task<T> Add<T>(E value,string typeName);


public class Test: IBaseRepository<SomeDefinedClass>

public Task<SomeClass> Add<SomeClass>(SomeDefinedClass value, string typeName)

throw new NotImplementedException();




Here is a solution for the problem, but there is still a problem in terms of how you are using it for repository pattern.

Does this look more like what you're after?

public interface IBaseRepository<R>

Task<T> Add<T>(R value, string typeName);


public class Test<R> : IBaseRepository<R>

public Task<T> Add<T>(R value, string typeName)

throw new NotImplementedException();




You only have to implement the method once. You just have to create a new Test<R> for each R you want to run.

Test<R>

R

I am sure that it will give you error that interface is not implemented.

As per your interface
Task Add(T value,string typeName);

Here if you look at correctly then Generic Type T must be in return Type Task and same way it should be input of Add function.

Now look at implementation

None of your method satisfy interface. For example

public Task Add(string value, string typeName)

Here T is SomeClass so your first argument of method must be of Type SomeType.

Update 1: I would do something like this.

public interface IBaseRepository<T,U,V>

Task<V> AddData(T namespaceName, U typeName);


public class SomeClass




public class Test : IBaseRepository<string, string, SomeClass> , IBaseRepository<int,string,SomeClass>

public Task<SomeClass> AddData(int namespaceName, string typeName)

throw new NotImplementedException();


public Task<SomeClass> AddData(string namespaceName, string typeName)

throw new NotImplementedException();




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