DeepLoad System.NullReferenceException - probably a newbie q

 Hi,

 Apologies for what is no doubt a newbie question - I have searched and found two threads here and here. However, they have not helped me solve my problem. In theory, my problem is more or less identical to the first link. 

I have two tables, Apartment and ApartmentType:

Apartment has

intApartmentID int primary key

intApartmentType int foreign key

vchApartmentName varchar

ApartmentType has

intApartmentType int primary key 

vchApartmentType varchar 

So, I want to get a collection of Apartments, deeploading the ApartmentType. I know that a record exists for IntApartmentID=6, I have ensured that the record in question has an existing record as its foreign key.

( edited for brevity)

        TList<Apartment> aptList = DataRepository.ApartmentProvider.Find("IntApartmentID=6");
        DataRepository.ApartmentProvider.DeepLoad(aptList, true, DeepLoadType.IncludeChildren, new Type[ { typeof(TList<ApartmentType>) });

        Response.Write(aptList[0].VchName + "<br />");
        Response.Write(aptList[0].IntApartmentTypeId + "<br />");
        Response.Write(aptList[0].IntApartmentTypeIdSource.VchApartmentType);  //   <-- Error is thrown by this line

 This results in "System.NullReferenceException: Object reference not set to an instance of an object." If I comment out the line, I can access the name and type.

I have also tried

      DataRepository.ApartmentProvider.DeepLoad(aptList, true, DeepLoadType.IncludeChildren, typeof(TList<ApartmentType>) );  

and

    DataRepository.ApartmentProvider.DeepLoad(aptList, true, DeepLoadType.IncludeChildren, typeof(ApartmentType) ); 

(the last, as it is a 1-->1 relationship)

 In each case, the  IntApartmentTypeIdSource.VchApartmentType is null.

 Coudl someone show me the error of my ways?

 Thanks,

Anthony 

* apologies for Hungarian notation, it is what I am used to- but it doesnt seem to fit .netTiers so well!

Well, I have fixed it, but it seems clumsy to me. I am now populating the apt.IntApartmentTypeIdSource manually - is that not what DeepLoad is supposed to do?

TList<Apartment> aptList = DataRepository.ApartmentProvider.Find("IntApartmentID=6");
        DataRepository.ApartmentProvider.DeepLoad(aptList, true, DeepLoadType.IncludeChildren, new Type[ { typeof(TList<ApartmentType>) });

        Response.Write(aptList[0].VchName + "<br />");
        Response.Write(aptList[0].IntApartmentTypeId + "<br />");

// Manually populate the  source:

       apt.IntApartmentTypeIdSource =
            DataRepository.ApartmentTypeProvider.GetByIntApartmentTypeId(apt.IntApartmentTypeId);

        Response.Write(apt.IntApartmentTypeIdSource.VchApartmentType); // Prints correct value.

 scudsucker,

If I understand correctly, I am pretty sure the command you were using: 

DataRepository.ApartmentProvider.DeepLoad(aptList, true, DeepLoadType.IncludeChildren, new Type[ { typeof(TList<ApartmentType>) });

was never going to work. Another one you tried (in your first post) is:

DataRepository.ApartmentProvider.DeepLoad(aptList, true, DeepLoadType.IncludeChildren, typeof(ApartmentType) ); 

This one I think should have worked. You are only trying to load one ApartmentType per  Apartment, so there is no need for the TList bit (If you were deep loading Apartments for an ApartmentType record, then you would use TList, as you are trying to load multiple Apartments for the ApartmentType).

I cant tell you why the deepload isnt working - but I try to avoid deeploads. I have found them to be a tad unreliable. One problem I found with deeploads that if the record I was deeploading was new, none of the children records would load.

 Hi, thanks. None of the methods I listed worked- and as I have a work-around, I wont pursue it too much.

 Deepload does seem like a cool feature, perhaps it is a little buggy still.