private initialized variable not initializing

Question

I have a datacontract on an inherited, partial class like this:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;

namespace Domain
{
  [DataContract]
  public partial class IdCard : DomainObject<System.Int64>
  {
    private Group _grp;

    [DataMember]
    public virtual Group Grp
    {
        get { return _grp; }
        set { _grp = value; }
    }

    private bool _unproxized = true;
    public override object UnProxy()
    {
        if (this._unproxized)  // this prevents stackoverflow with cyclical references
        {
            this.Grp = (Group)this.Grp.UnProxy();
            this._unproxized = false;
        }

        return this;
    }
  }
}

For some reason, the _unproxized is never set to true; Any ideas why?

I know I can simply switch the logic around, but I'm curious why the member variable is not being initialized.

Sorry to ask, but how did you come to the conclusion that it isn't being initialized? — Brian Rasmussen, Jan 18 '11 at 19:18
First, I know that a boolean defaults to false. Second, the code inside the conditional is never getting called. Third, when I inspect it with a debugger during the conditional it is false. — Lucas B, Jan 18 '11 at 20:09
"private initialized variable not initializing". The title of the question is a paradox. — , Jan 20 '11 at 05:48

score 4 · Accepted Answer · edited May 23 '17 at 10:33

4

Has the instance that you are looking at been deserialized? During standard DataContract de-serialization no constructors are called and only DataMembers are assigned. The variable that you are looking at is not marked as a DataMember.

This thread describes the implementation of the behavior that you are seeing using an almost identical example.

edited May 23 '17 at 10:33

Community

1
1

answered Jan 20 '11 at 04:18

ErnieL

5,773
1
23
27

score 2 · Answer 2 · edited Nov 06 '12 at 15:35

2

It's because when deserialising, the DataContract serialiser uses a type of reflection to create completely uninitialised object instances, to which it then applies data. That's why the DataContract serialiser doesn't require a parameterless constructor. (Even if you add one, it won't get called). If you mark the _unproxied field with a [DataMember] attribute, it will be true.

edited Nov 06 '12 at 15:35

Boeckm

3,264
4
36
41

answered Nov 06 '12 at 15:08

Dan

21
1

Nice explanation and it sounds rational, do you have any references to support that? It sounds like a bug to me that should be reported to MS bug tracker (connect.microsoft.com) – Lucas B Nov 07 '12 at 17:48

score 0 · Answer 3 · answered Jan 18 '11 at 19:16

0

My suspicion is you are using web/service references. In this case the code (private variable) never gets to the client.

answered Jan 18 '11 at 19:16

Aliostad

80,612
21
160
208

You are correct, however, I'm talking about the server side variable. – Lucas B Jan 18 '11 at 20:06

score 0 · Answer 4 · answered Jan 18 '11 at 19:21

0

try to assign varibles in a constructor like this:

public IdCard()
{
    _unproxized = true;
}

answered Jan 18 '11 at 19:21

Agreed, that is a solution. I'm not asking for a solution though, I'm asking why it is not being initialized. – Lucas B Jan 18 '11 at 20:07

private initialized variable not initializing

4 Answers4