I'm trying to do this:

using(var context = new SampleEntities()) 
{ 
     User user = select a user from database; 

     //Update user's properties 
     user.Username = ... 
     user.Website = ... 

     //Add a role 
     Role role = select a role from database 
     //trying to insert into table UserRoles which has columns (UserID, RoleID) 
     user.Roles.Add(role); 

     //Apply property changes 
     context.ApplyPropertyChanges("Users", user); 
     context.SaveChanges(); 
}

However, I get an exception telling me that "The existing object in the ObjectContext is in the Added state" and can't "ApplyPropertyChanges". If "ApplyPropertyChanges()" is removed, it adds a User.

What orders should these methods be called? I don't need to do them separately right?

Thanks.