How to work with DTOs in Controller of WebAPI?

Simply put, your new edit indicates you don't needId and Member residences in yourAddressDTO model. And you should mould the outcome into aList<AddressDTO> when you are heading backList<Address> .

Therefore, merely delete any unnecessary attributes fromAddressDTO You then mould the outcome by making new choicesAddressDTO and setting properties:

var result = db.Address.Select(x=> new AddressDTO()
                                   { 
                                       Street = x.Id, 
                                       Street_Number = x.Street_Number,
                                       City = x.City,
                                       Country = x.Country
                                   }).ToListAsync();

You may add such a function Object() { [native code] } to the linq to make it shorter.AddressDTO :

public AddressDTO(Address x)
{
    Street = x.Id;
    Street_Number = x.Street_Number;
    City = x.City;
    Country = x.Country;
}

and in the controller:

var result = db.Address.Select(x=> new AddressDTO(x)).ToListAsync();

You may depend on certain object mappers, such as auto mapper, as described in a response, even while working on a big project.