EntityKey and ApplyPropertyChanges()

Question

I need to set an EntityObject\'s EntityKey. I know its type and its id value. I don\'t want to query the database unnecessarily.

This works...

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Answer 1

public static class EfExtensions
{
    public static void ApplyDetachedPropertyChanges(this ObjectContext db, T entity, Func getIdDelegate)
    where T : EntityObject
    {
        var entitySetName = db.DefaultContainerName + "." + entity.GetType().Name;

        T newEntity = Activator.CreateInstance();
        newEntity.EntityKey = db.CreateEntityKey(entitySetName, entity);

        Type t = typeof(T);
        foreach(EntityKeyMember keyMember in newEntity.EntityKey.EntityKeyValues) {
            PropertyInfo p = t.GetProperty(keyMember.Key);
            p.SetValue(newEntity, keyMember.Value, null);
        }

        db.Attach(newEntity);
        //db.AcceptAllChanges();

        db.ApplyPropertyChanges(entitySetName, entity);
    }
}