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I am having some troubles connecting to my database in Entity Framework6, using Code First approach.

Instead of connecting to my local DB that gets created in the App_Data folder, I have set up my connection string to point to a empty Database (no tables) in SQL Server.

Here is my connection string:

<add name="LiquorContext" connectionString="Data Source=.; Initial Catalog=MVC_Code_First;User ID=sa; Password=*******;" providerName="System.Data.SqlClient" /> 

Whenever this line gets called in my ViewModel, I get the "System.ArgumentNullException: Value cannot be null. Parameter name: source" error:

var users = context.Users.ToList(); 

Could this possibly be that my Seed method is not being called, as I have placed a breakpoint there, but never gets reached?

Here is my Context class:

public class LiquorContext : DbContext { public LiquorContext() : base("LiquorContext") { } public DbSet<ExampleUser> Users; protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Conventions.Remove<System.Data.Entity.ModelConfiguration.Conventions.PluralizingTableNameConvention>(); } } 

Here is my ContextInitializer:

public class LiquorContextInitializer : DropCreateDatabaseIfModelChanges<LiquorContext> { protected override void Seed(LiquorContext context) { var users = new List<ExampleUser>() { new ExampleUser { Name="a", Surname="b"}, new ExampleUser { Name="c", Surname="d"}, new ExampleUser { Name="e", Surname="f"}, new ExampleUser { Name="g", Surname="h"} }; foreach (var user in users) { context.Users.Add(user); } context.SaveChanges(); } } 

Here I call the Initializer in the Global.asax file:

protected void Application_Start() { Database.SetInitializer<LiquorContext>(new LiquorContextInitializer()); AreaRegistration.RegisterAllAreas(); FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters); RouteConfig.RegisterRoutes(RouteTable.Routes); BundleConfig.RegisterBundles(BundleTable.Bundles); } 

Any help would be appreciated. Thanks

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2 Answers 2

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In my LiquorContext class, I had the DbSet<> as follow:

public DbSet<ExampleUser> Users; 

By adding the { get; set; } as follow, it works:

public DbSet<ExampleUser> Users { get; set; } 
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Comments

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Without more information is hard to say. Did you set a database initializer in the constructor for your context? This might help:

http://www.codeproject.com/Articles/794187/Various-Strategies-to-Initialize-Database-in-Entit

1 Comment

Thanks. I have edited my question now. Having a look at the link you provided.