ObjectDisposedException on Foreign entity

Question

I'm quite a newbie with Linq to Sql, and I'm facing an issue regarding accessing a foreign entity. Here is the related DB :

Table MyClass with two columns : Id, ProducerId
Table Person with two columns : Id, Affix

Here is my partial class :

public partial class MyClass
{
    public string ProducerAffix
    {
        get { return Producer.Affix; }
    }
}

And the dbml designer file where the Producer property is generated related to ProducerId foreign key :

[global::System.Data.Linq.Mapping.AssociationAttribute(Name="Person_MyClass1", Storage="_Person1", ThisKey="ProducerId", OtherKey="Id", IsForeignKey=true)]
    public Person Producer
    {
        get
        {
            return this._Person1.Entity;
        }
        set
        {
            Person previousValue = this._Person1.Entity;
            if (((previousValue != value) 
                        || (this._Person1.HasLoadedOrAssignedValue == false)))
            {
                this.SendPropertyChanging();
                if ((previousValue != null))
                {
                    this._Person1.Entity = null;
                    previousValue.MyClass.Remove(this);
                }
                this._Person1.Entity = value;
                if ((value != null))
                {
                    value.MyClass.Add(this);
                    this.ProducerId = value.Id;
                }
                else
                {
                    this.ProducerId = default(System.Guid);
                }
                this.SendPropertyChanged("Producer");
            }
        }
    }

When accessing MyClass' Affix property, an ObjectDisposedException is thrown... Do I need to open a Datacontext when accessing the property ?

I read this post LINQ to SQL ObjectDisposedException on entity that never asked for but really would like avoiding creating a ViewModel... Is there any other solution ?

Thanks a lot !

EDIT

Following JAT's answer I tried to use the DLO but don't really know how to return my foreign value from it... I found this tutorial (http://www.codeproject.com/Articles/37857/Optimizing-LINQ-Queries-using-DataLoadOptions), do I have to write a query then ?

public string Affix
    {
        get
        {
            using (var db = new DBDataContext())
            {
                var dlo = new DataLoadOptions();
                dlo.LoadWith<Person>(p => p.Affix);
                db.LoadOptions = dlo;
                ...
                return Producer.Affix;
            }
        }
    }

If you want to have access to related entities after the context has been disposed you can use [DataLoadOptions](https://msdn.microsoft.com/en-us/library/system.data.linq.dataloadoptions.aspx) — The One, Feb 19 '15 at 18:25
http://stackoverflow.com/questions/5783109/in-linq-to-sql-how-do-i-include-the-child-entity-with-initial-query — The One, Feb 19 '15 at 18:25

score 0 · Accepted Answer · answered Feb 27 '15 at 16:00

For those who might face the same issue later, I finally found out where this came from. When I added my Person and my MyClass, I used this function :

public static Person Add(Person person)
{
    using (var db = new DBDataContext())
    {
        db.Person.InsertOnSubmit(person);
        db.SubmitChanges();
        return person;
    }
}

Removing the "using" did the trick for me and now I can access my foreign keys' entities. I sincerely don't understand why because I read that "using" was a better solution than "new" because of the close issue, but seems like it does not work correctly with it, so I removed it.

public static Person Add(Person person)
{
    var db = new DBDataContext();

    db.Person.InsertOnSubmit(person);
    db.SubmitChanges();
    return person;

}

ObjectDisposedException on Foreign entity

1 Answers1