Question

at first I want to make my apologize for my english

I’ve a problem with DTOs, I’m using SQLAzure for my DB and I host services on Azure

Some of my objects have ICollection of other objects, typically a country(Country Table) has a collection of airports (Airport Table), I use Entity Framework for DB Connection and DTO for present my object

A this point everything fine but on the client side when I want to use the property Icollection of an object, VS says “ambiguous name”, it seems during the serialization it re-type my object

I’ve DTOAirport on server side

I’ve two sorts of airport on client side after serialization
first the airportservice.airportClient.DTOAirport
second the countryService.countryClient.DTOAirport

I can’t use my classic DTOAirport and it dont support cast…

I’ve a lot of problems whith it, that I don’t have on “classics WCF services”

I can post code if you want it

Thanks a lot for reading me

{
[DataContract]
public class DTOAirport
{
    [DataMember]
    public int IdAirportDTO { get; set; }

    [DataMember]
    public string NameAirportDTO { get; set; }

    [DataMember]
    public string IATACodeDTO { get; set; }

    [DataMember]
    public string ICAOCodeDTO { get; set; }

    [DataMember]
    public string ZoneDTO { get; set; }

    [DataMember]
    public int FKCountryDTO { get; set; }

    [DataMember]
    public string CityDTO { get; set; }

    [DataMember]
    public double LatitudeDTO { get; set; }

    [DataMember]
    public double LongitudeDTO { get; set; }

    [DataMember]
    public Nullable<int> AltitudeDTO { get; set; }
}

}

{
[DataContract]
public class DTOCountry
{
    [DataMember]
    public int IdCountryDTO { get; set; }

    [DataMember]
    public string NameCountryDTO { get; set; }

    [DataMember]
    public ICollection<DTOAirport> AirportsListDTO { get; set; }
}

}

Here are my DTOs, I use a mapper for map it on Entity Framework classes

this is a typical service on server side

        public DTOAirport GetAirportById(int idAirport)
    {
        using (FlexAzureContainer1 context = new FlexAzureContainer1())
        {
            DTOAirport airport = new DTOAirport();
            airport = DTOAirportMapper.MapFrom(context.DM_AIRPORTS.Where(a => a.IdAirport == idAirport).FirstOrDefault());
            return airport;
        }
    }

        public DTOCountry GetCountryById(int idCountry)
    {
        using (FlexAzureContainer1 context = new FlexAzureContainer1())
        {
            DTOCountry country = new DTOCountry();
            country = DTOCountryMapper.MapFrom(context.DM_COUNTRIES.Where(c => c.IdCountry == idCountry).FirstOrDefault());
            return country;
        }
    }

here is a Console test on client side and the errors it gaves me

public class Program
{
    static AirportService.AirportServiceClient myAirportService = new AirportService.AirportServiceClient();
    static CountryService.CountryServiceClient myCountryService = new CountryService.CountryServiceClient();

    public static void Main(string[] args)
    {
         List<DTOAirport>airportsList = myCountryService.GetCountryById(1).AirportsListDTO.ToList();
        DTOCountry country = myCountryService.GetCountryById(1);    
        DTOAirport airport = myAirportService.GetAirportById(1);
        foreach (DTOAirport airport2 in country.AirportsListDTO.ToList())
        {
            Console.WriteLine(airport2.NameAirportDTO);
        }
        Console.WriteLine(country.NameCountryDTO);
        Console.WriteLine(airport.NameAirportDTO);
        Console.ReadLine();

    }
}

}

Error   1   Cannot implicitly convert type 'System.Collections.Generic.List<FlexinergieAircraft.Client.CountryService.DTOAirport>' to 'System.Collections.Generic.List<FlexinergieAircraft.Client.DTOAirport>'  D:\Projects\FlexinergieAicraft.OldVersions\FlexinergieAircraft17\FlexinergieAircraft\FlexinergieAircraft.Client\FlexinergieAircraft.Client\Program.cs   17  45  FlexinergieAircraft.Client

Error   2   Cannot implicitly convert type 'FlexinergieAircraft.Client.CountryService.DTOCountry' to 'FlexinergieAircraft.Client.DTOCountry'    D:\Projects\FlexinergieAicraft.OldVersions\FlexinergieAircraft17\FlexinergieAircraft\FlexinergieAircraft.Client\FlexinergieAircraft.Client\Program.cs   18  34  FlexinergieAircraft.Client

Error   3   Cannot implicitly convert type 'FlexinergieAircraft.Client.AirportService.DTOAirport' to 'FlexinergieAircraft.Client.DTOAirport'    D:\Projects\FlexinergieAicraft.OldVersions\FlexinergieAircraft17\FlexinergieAircraft\FlexinergieAircraft.Client\FlexinergieAircraft.Client\Program.cs   19  34  FlexinergieAircraft.Client

If you need something else

In this exemple exemple I test whith DTOs on Client side, the result was same, it seems the service re-type the objects

Maybe it is the proxy but it not mades a long time I work on azure and .NET in general

Answer 1

Your error message has a path which includes “.oldversions”.

Is there a chance that the client and server are two different versions?

Also I see that you have a nullable int, sometimes nullable types can be a problem. You could try it without this field just in case.