asp.net mvc code first using db context object throws null reference exception

Question

i have a strange problem with same code on a different pc. This is a mvc3 code first project.

I downloaded my project from svn. pressed build button. as usual, db initializer method has been called and started to execute. it created few tables with some data. no problem. as you can see :

Here is some screenshots, execution of the code, sorry cant post here since i need rep. img #0-#1-#2)

However to create users for the application, i decided to do it in a repository class. therefore i call my create method within initializer, Here is my usercreate function :

public MembershipUser CreateUser(string username, string firstname, string lastname, string password, string email)
    {
        using (KlmsnContext db = new KlmsnContext())
        {
            User user = new User();

            user.UserName = username;
            user.FirstName = firstname;
            user.LastName = lastname;
            user.Email = email;
            user.PasswordSalt = CreateSalt();
            user.Password = CreatePasswordHash(password, user.PasswordSalt);
            user.CreatedDate = DateTime.Now;
            user.IsActivated = false;
            user.IsLockedOut = false;
            user.LastLockedOutDate = DateTime.Now;
            user.LastLoginDate = DateTime.Now;

            db.Users.Add(user);

    db.SaveChanges();

            return GetUser(username);
        }
    }

However in "using block" (statement) when i look closely my new db object throws null reference for every entities,

screenshot img #3-#4

..and adding a user fails accordingly with the same " Object reference not set to an instance of an object " error. Strangely, the exact same code runs without error on a different computer. with almost same setup and os.

Any ideas on whats causing this? thanks!

update #1: StackTrace :

    (InternalContext c)
   at System.Data.Entity.Internal.RetryAction`1.PerformAction(TInput input)
    at System.Data.Entity.Internal.RetryAction`1.PerformAction(TInput input) at
    System.Data.Entity.Internal.LazyInternalContext.InitializeDatabaseAction(Action`1
    action)
    at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabase()
    at
    System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type
    entityType)
    at System.Data.Entity.Internal.Linq.InternalSet`1.Initialize()
    at System.Data.Entity.Internal.Linq.InternalSet`1.get_InternalContext()
    at System.Data.Entity.Internal.Linq.InternalSet`1.ActOnSet(Action action, EntityState newState, Object entity, String methodName) at System.Data.Entity.Internal.Linq.InternalSet`1.Add(Object entity) at System.Data.Entity.DbSet`1.Add(TEntity entity) at Klmsncamp.Models.UserRepository.CreateUser(String username, String firstname, String lastname, String password, String email) in C:\Users\Hp\Documents\Visual Studio 2010\Projects\Project2Klmsan\Klmsncamp\Models\UserRepository.cs:line 31 at Klmsncamp.DAL.KlmsnInitializer.Seed(KlmsnContext context) in C:\Users\Hp\Documents\Visual Studio 2010\Projects\Project2Klmsan\Klmsncamp\DAL\KlmsnInitializer.cs:line 212 at System.Data.Entity.DropCreateDatabaseAlways`1.InitializeDatabase(TContext
    context)
    at
    System.Data.Entity.Database.c__DisplayClass2`1.b__0(DbContext
    c)
    at
    System.Data.Entity.Internal.InternalContext.c__DisplayClass5.b__3()
    at
    System.Data.Entity.Internal.InternalContext.PerformInitializationAction(Action
    action)
    at
    System.Data.Entity.Internal.InternalContext.PerformDatabaseInitialization()
    at
    System.Data.Entity.Internal.LazyInternalContext.b__4(InternalContext
    c)
    at System.Data.Entity.Internal.RetryAction`1.PerformAction(TInput input)

Do you have different databases for the computers? Perhaps db.Roles.Find(3) is the problem — Pleun
– Pleun, Commented Feb 11, 2013 at 18:17
I'm home now. i can paste stack trace tomorrow tho :S. @pleun: nope it s same, sqlexpress. <connectionStrings> <add name="KlmsnContext" connectionString="Data Source=.\sqlexpress;Initial Catalog=klmsncamp;Integrated Security=True;MultipleActiveResultSets=True" providerName="System.Data.SqlClient" /> </connectionStrings> — Zusa
– Zusa, Commented Feb 11, 2013 at 19:12
Can you please post the User class, and the full stack trace? — Corey Adler
– Corey Adler, Commented Feb 11, 2013 at 19:24

Amirhossein Mehrvarzi · Accepted Answer · 2014-02-23 15:33:24Z

0

Can you at least show me your DbContext class , I think you probably didn't set your property to DBset Type

public class EnocDB : DbContext
  {
      public DbSet<EnocParcels> Parcels { get; set; }
      public DbSet<ReviewEnoc> Reviews { get; set; }
  }

edited Feb 23, 2014 at 15:33

Amirhossein Mehrvarzi

19.1k7 gold badges52 silver badges74 bronze badges

answered Feb 23, 2014 at 15:11

el3shry

11 bronze badge

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