DataContractSerializer skip OpenAccess Version's value

Question

Hi,

I'm using OpenAccess disconnected model. When I try to deserialize an object with DataConractSerializer, the Version property of this object is 0 - but only in the xml. If I debug the code and watch the value - it's 1 (or 2,3...)

If I say before the serialization "int temp = object.Version" the seriazlier can save the value.

There is a lazy issue, I'm sure. How can I force to read/save this value without explicit calls?

Code snippets: http://www.telerik.com/community/forums/orm/general-discussions/objectnetworkattacher-vs-datacontractserializer.aspx#775451

Answer 1

It sounds like the [DataMember] is set against the field (or is defaulting to fields), and is bypassing the lazy behaviour. If you control the type, you could perhaps add an [OnSerializing] method that peeks at this property before serialization kicks in... that way it should have a value, and you won't need to put code into other places.

If the type is generated, look to see if it is a partial class. If so, you can add another partial class of the same name (and same namespace), and put your [OnSerializing] method in there...

Example (uncomment the last block to make it work):

using System;
using System.Runtime.Serialization;
using System.Xml;

class Program {
    static void Main() {
        using (XmlWriter writer = XmlWriter.Create(Console.Out)) {
            new DataContractSerializer(typeof(Foo))
                .WriteObject(writer, new Foo());
        }       
    }
}

[DataContract]
partial class Foo {
    [DataMember(Name="Bar")]
    private int? bar;
    public int Bar {
        get {
            if (bar == null) bar = 27; // somthing lazy
            return bar.GetValueOrDefault();
        }
        set { bar = value; }
    }
}
/* UNCOMMENT THIS
partial class Foo {
    [OnSerializing]
    private void BeforeSerialize(StreamingContext ctx) {
        int tmp = Bar;
    }
}
*/

Answer 2

Hi, you should call the .Retrieve() method on your object which will load all the lazy-loaded fields and you will have all the data required for serialization. Hope that helps.