Question

Im using a seperate business logic class to get my Data Object from the database,

public partial class HelperUsers
{
    public User GetUser(string Username, string Password)
    {

        using (var myEntities = new BusinessLogic.Entities())
        {
            var query = (from u in myEntities.Users
                         join link in myEntities.linkUserPhoneNumbers on u.UserId equals link.UserId
                         join p in myEntities.PhoneNumbers on link.PhoneNumberId equals p.PhoneNumberId
                         where u.UserName == Username && u.Password == Password
                         select u).ToList();



            if (query.Any())
                return (User)query[0];
        }
        return null;

    }
}

This works well however when using on my calling page

  protected void btnLoad_OnClick(object sender, EventArgs e)
  {
        HelperUsers helper = new HelperUsers();
        var myUser            helper.GetUser("username", "password")
        // This works fine 
        lblUserName.Text =  myUser.Username
        // If i try to read one of the child objects from the join it returns an error
        if (myUser.linkUserPhoneNumbers.Any())
        {
            //do something
        }
  }

The error i get is

 The ObjectContext instance has been disposed and can no longer be used for operations that require a connection.

Anyone know a way around this, so that i can access all the info in my user object.

Answer 1

If you use this declaration:

using (var myEntities = new BusinessLogic.Entities())

then you can’t use myUser.linkUserPhoneNumbers.Any() afterwards because linkUserPhoneNumbers is not loaded and the context is disposed. You need to include linkUserPhoneNumbers in the query or keep the context undisposed.
Look here: http://msdn.microsoft.com/en-us/library/bb896272.aspx