Hello again,

I have a OwnerEntity that has one to many properties. I am return a collection of ownerentities including the properties from a webservice using writexml.

I am reading on the client side using readxml and getting the following error.

System.ArgumentException: Object of type 'CREToolkit.data.EntityClasses.OwnerEntity' cannot be converted to type 'CREToolkit.data.EntityClasses.MyOwnerEntity'. at System.ComponentModel.ReflectPropertyDescriptor.SetValue(Object component, Object value) at SD.LLBLGen.Pro.ORMSupportClasses.XmlHelper.SetReadReferences(List1 nodeEntityReferences, Dictionary2 processedObjectIDs) at SD.LLBLGen.Pro.ORMSupportClasses.EntityCollectionBase21.ReadXml(XmlNode node) at SD.LLBLGen.Pro.ORMSupportClasses.EntityCollectionBase21.ReadXml(String xmlData) at CreToolkit.UIWebSellers.LoadWorker_DoWork(Object sender, DoWorkEventArgs e) in C:\Documents and Settings\Thomas Belknap\My Documents\Visual Studio 2005\Projects\CreToolkit\UserControls\Websites\UIWebSellers.vb:line 215

I know this has something to do with the properties being included. I tested just returning the ownerentities without the properties and it worked.

Thanks,

Thomas

Please post more info: 1- RuntimeLibrary version? 2- Post the code of the webService that performs the WriteXML, and the code at the client that performs the ReadXML.

Make sure the server and client apps are using the same version of the generated assemblies/code.

Note: generics(EntityCollection<OwnerEntity>) aren't supported in webservices nor are polymorphic fetches. This means that the type returned by the webmethod is the type of object you will get on the client. If you return an instance of a derived type of the webmethod's returntype (e.g. you return a ManagerEntity while the method's returntype is EmployeeEntity, you'll get an EmployeeEntity object at the client, not a ManagerEntity object.

Runtime v2.0.50727

I am getting the correct entity that I want.

OwnerEntity has many PropertyEntity. I am prefetching my PropertyEntityCollection when I get my OwnerEntityCollection on the webservice.

I write the xml from the OwnerEntity Collection on the webservice.

On the client I have a collection of OwnerEntity type. I read in the xml there and that is where i get the casting error.

When I stopped prefetching the PropertyEntityCollection on the webservice and just returned the OwnerEntityCollection everything worked.

It has something to do with my prefetch. Here is the code for that.

        Dim Sellers As New EntityCollection(Of OwnerEntity)

        Dim Prefetch As IPrefetchPath2 = New PrefetchPath2(CInt(EntityType.OwnerEntity))
        Prefetch.Add(OwnerEntity.PrefetchPathPropertyLead)

        Using adapter As New DataAccessAdapter
            adapter.ConnectionString = Connection
            adapter.FetchEntityCollection(Sellers, Nothing, Prefetch)
            adapter.CloseConnection()
        End Using

        Prefetch = Nothing

        Return Sellers

It works when I take out the prefetch.

Thomas

Please rightclick the ORMSupportClasses dll in windows explorer -> properties -> Version tab, that's the version, e.g. 2.0.0.061205

Also, it seems you're using adapter with derived entities, be sure to use these on BOTH sides.

Otis wrote:

Please rightclick the ORMSupportClasses dll in windows explorer -> properties -> Version tab, that's the version, e.g. 2.0.0.061205

Also, it seems you're using adapter with derived entities, be sure to use these on BOTH sides.

2.0.0.061023

I think that is the problem. I don't think I set up the entitycollection correctly on my client.

I am not sure how to set it up to allow me to read in the derived entities from xml.

Right now it is only a EntityCollection(of OwnerEntity)

What do I need to do to set it up to allow for my propertycollection?

Thomas

Any ideas on how I should be creating my EntityCollection on the client to allow for my derived entities?

Thomas

System.ArgumentException: Object of type 'CREToolkit.data.EntityClasses.OwnerEntity' cannot be converted to type 'CREToolkit.data.EntityClasses.MyOwnerEntity'.

Did you make sure you are using the same version of the generated code on both sides (server & client)? Does both sides have MyOwnerEntity defined?

2- Post the code of the webService that performs the WriteXML, and the code at the client that performs the ReadXML.

Please

Yes, same version on both the client and server.

Server code:

    Dim sellerXml As String = String.Empty

    Dim Sellers As EntityCollection(Of OwnerEntity) = TigerBuyingWebsite.GetSellers(Setting.GetConnection)

    If Not Sellers Is Nothing Then

        Sellers.WriteXml(XmlFormatAspect.Compact, sellerXml)
        Return sellerXml

    Else

        Return ""

    End If

Client Code:

        Sellers.Clear()
        Sellers = New EntityCollection(Of OwnerEntity)
        Sellers.ReadXml(WebService.GetSellers)

Thanks,

Thomas

As you use derived entities, you have to use: Prefetch.Add(MyOwnerEntity.PrefetchPathPropertyLead)

instead. Otherwise it uses the OwnerEntity's prefetch path and inserts the PropertyLeadEntity's factory instead of the MyPropertyLeadEntity's factory.

This is what I am using on the server side now.

        Dim Sellers As New EntityCollection(Of OwnerEntity)

        Dim Prefetch As IPrefetchPath2 = New PrefetchPath2(CInt(EntityType.OwnerEntity))
        Prefetch.Add(MyOwnerEntity.PrefetchPathPropertyLead)

        Using adapter As New DataAccessAdapter
            adapter.ConnectionString = Connection
            adapter.FetchEntityCollection(Sellers, Nothing, Prefetch)
            adapter.CloseConnection()
        End Using

        Prefetch = Nothing

        Return Sellers

I am still getting the same error. Do I need to do anything with my client side code to allow for the PropertyLeadCollection?

Thomas

I think I see what's the problem. You also need to do: Dim Sellers As New EntityCollection(Of MyOwnerEntity)

Or better: Dim Sellers As New EntityCollection(Of MyOwnerEntity)(New MyOwnerEntityFactory())

as the error comes from the fact that the PropertyLead.Owner property is set to an Owner instance (as you specified 'OwnerEntity') but the MyPropertyLead class has that property defined as a property of the type MyOwnerEntity.