Entity Framework does not save all changes

Question

Im very close to tears on this one.

I have a user-object this object has several properties FirstName, LastName etc. all simple types. String int etc.

These get loaded and updated fine.

public class Jobwalker
{
    [Key]
    public Int64 ID { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
    public bool Suspended { get; set; }
    public TelephoneCountryCode TelephoneCountryCodeObject { get; set; }
    ...

But the userobject also has a property 'TelephoneCountryCodeObject' which is another class

public class TelephoneCountryCode
{
    [Key]
    public Guid ID { get; set; }
    public string Code { get; set; }
    public string Country { get; set; }

    public TelephoneCountryCode()
    {
    }
    ...

I can create delete an dmodify 'TelephoneCountryCode'-objects just fine, but when i try to save an instance of a user-object only the simple types gets updated?

public void Save()
    {
        try
        {
            using (var db = new MainContext())
            {

                db.TelephoneCountryCodes.Attach(TelephoneCountryCodeObject);
                Jobwalker result = (from jw in db.Jobwalkers
                                        .Include("TelephoneCountryCodeObject")
                                    where jw.UmbracoMemberID == UmbracoMemberID
                                    select jw).FirstOrDefault();


                db.Entry(result).CurrentValues.SetValues(this);

                if (this.TelephoneCountryCodeObject != null)
                {
                    result.TelephoneCountryCodeObject = db.TelephoneCountryCodes.Find(this.TelephoneCountryCodeObject.ID);
                }
                else
                {
                    result.TelephoneCountryCodeObject = null;
                }

                db.Entry(result).State = EntityState.Modified;

                db.SaveChanges();
            }
        }
        catch(Exception ex)
        {
            throw;
        }
    }

Any ideas would be greatly appreciated!

EDIT: I created this super simple test method

 public static void TEST()
    {
        try
        {
            using (var db = new MainContext())
            {
                Jobwalker result = (from jw in db.Jobwalkers
                                        .Include("TelephoneCountryCodeObject")
                                    where jw.UmbracoMemberID == 1184
                                    select jw).FirstOrDefault();



                result.TelephoneCountryCodeObject = TelephoneCountryCode.GetByName("denmark");
                db.TelephoneCountryCodes.Attach(result.TelephoneCountryCodeObject);
                result.FirstName = "Flemming";

                db.SaveChanges();
            }
        }
        catch (Exception ex)
        {
            throw;
        }
    }

This works like it is supposed to. Then why the * * wont my regular Save() method work?

Answer 1

If you need to update an entity which is detached (for example you instantiated the object without fetching from database), you should have it's primary key and use the code below:

public void Update(Jobwalker detachedEntity)
{
    DB.Jobwalkers.Attach(detachedEntity);
    DB.Entry(detachedEntity).State = EntityState.Modified;
}

// in your code to save Jobwalker detached object do this:
Update(this); // `this` is the Jobwalker detached object
DB.SaveChanges();

There is no need for extra code, EF will detect your changes and update the entity and add the child entities to database.

Answer 2

This is more than likely a result of TelephoneCountryCodeObject not being a dynamic proxy from the database, and probably just being a plain object. I believe that if you attach the result, then you will be able to save the changes.

Jobwalker result = (from jw in db.Jobwalkers
  .Include("TelephoneCountryCodeObject")
  where jw.UmbracoMemberID == UmbracoMemberID
  select jw).FirstOrDefault();
db.TelephoneCountryCodes.Attach(result);