c# LINQ to Entities: retrieve custom objects

I've got an easy entity model

Bank 1---∞ User 1---∞ Session

In partial class Bank i've got to store an object Clock set during Bank creation. Is it possible to retrieve this Clock object from inside a Session method and, of course, no Bank parameter passed?

Some code

public partial class Bank : IBank { private IClock _bankClock;

    public IClock Clock
    {
        get { return _bankClock; }
        set { _bankClock = value; }
    } 

}

public partial class Session : ISession public bool MyMethod() { var test = (dc.Session.Include("User.Bank").Where(t => t.session_id == session_id)); var temp = test.First().User.Bank.Clock.Now(); }

when calling MyMethod i get Object reference not set to an instance of an object. and it is referred to the Clock property. Have you got any hints to retrieve a custom object from a LINQ query?

Thank you, Best Regards

more code //CreateBank

public IBank CreateBank(string bankName, int 开发者_运维问答valuePassedInCreateMethod, Clock bankClock) {using (var dc = new Database1Entities(Functions.ToEntitiesConnectionString(connectionString))) { _dbField=valuePassedInCreateMethod; bankReturn=(from c in dc.Bank where c.bank_name == bankName select c).First(); bankReturn.Clock = bankClock; dc.SaveChanges(); return bankReturn;

            }

}

Check object creation _bankClock, have you assigned some value to it?

See if I am close to your requirement. I get this working

   static class Program
{
    [STAThread]
    static void Main()
    {
        User user = new User();
        user.Bank = Bank.CreateBank("my bank", 23, new Clock());
        Session session = new Session(user, "myid");
        bool returned = session.MyMethod();
        if (returned)
            MessageBox.Show("Got it");
    }

}

public class Bank
{

    int value;
    string bankName;
    public Clock Clock;

    public static Bank CreateBank(string bankName, int valuePassedInCreateMethod, Clock bankClock)
    {
        Bank b = new Bank();
        b.Clock = bankClock;
        b.bankName = bankName;
        b.value = valuePassedInCreateMethod;
        return b;
    }
}

public class User
{
    public Bank Bank;
    public string type = "User.Bank";
}

public partial class Session
{

    public static List<Session> Sessions;
    string type;
    string session_id;
    User User;

    public Session(User user, string session_id)
    {
        if (Sessions == null) Sessions = new List<Session>();
        this.User = user;
        this.type = user.type;
        this.session_id = session_id;
        Sessions.Add(this);
    }

    static void Add(Session session)
    {
        Sessions.Add(session);
    }
    static List<Session> Include(string type)
    {
        return Sessions.Where(rs => rs.type == type).ToList<Session>();
    }
    public bool MyMethod()
    {
        var test = Session.Include("User.Bank");
        var test1 = test.Where(t => t.session_id == session_id);
        var temp = test1.First();
        var temp1 = temp.User;
        var temp2 = temp1.Bank;
        var temp3 = temp2.Clock;
        var temp4 = temp3.Now();
        if (temp4 != DateTime.MinValue)
            return true;
        return false;
    }
}
public class Clock
{
    public DateTime Now()
    {
        return DateTime.Now;
    }
}