EF4 Context.ApplyCurrentValues ​​does not update current values

Question

I have an entity that I extract as follows and is separate from the context:

ctx.Reviews.MergeOption = MergeOption.NoTracking;

Review review = (from r in ctx.Reviews.Include("ReviewNotes")
                 where r.ReviewID == reviewID
                 select r).First();

Then I make changes to the object with respect to:

if (review.ReviewNotes.Count > 0)
{
  ReviewNote r = review.ReviewNotes.ElementAt(0);
  r.Note = "Ugg " + DateTimeOffset.Now.ToString();
  r.CreatedDate = DateTimeOffset.Now;
}

Then I attach the object and loop the children and change its state of the entity, if necessary. When saving changes, nothing is updated .:

ctx.Reviews.Attach(review);
foreach (ReviewNote item in review.ReviewNotes)
{
   if (item.ReviewNoteID == 0)
   {
       ctx.ObjectStateManager.ChangeObjectState(item, EntityState.Added);
   }
   else
   {
       key = ctx.CreateEntityKey("ReviewNotes", item);
       if (ctx.TryGetObjectByKey(key, out original))
       {
           ctx.ApplyCurrentValues<ReviewNote>(key.EntitySetName, item);
       }

   }
 }

ctx.ObjectStateManager.ChangeObjectState(review, EntityState.Modified);
ctx.SaveChanges();

Answer 1

MergeOption.NoTracking, Detached. . , EntityState - . , , : . SaveChanges.

, ApplyCurrentValues:
EntityKey . .
, , , ReviewNote , EF :

ctx.Reviews.Attach(review);
foreach (ReviewNote item in review.ReviewNotes) {
   if (item.ReviewNoteID == 0) {
       ctx.ObjectStateManager.ChangeObjectState(item, EntityState.Added);
   }
   else {
       key = ctx.CreateEntityKey("ReviewNotes", item);
       if (ctx.TryGetObjectByKey(key, out original)) {
           // ctx.ApplyCurrentValues(key.EntitySetName, item);
           ctx.ObjectStateManager.ChangeObjectState(item, EntityState.Modified);
       }
   }
 }
ctx.ObjectStateManager.ChangeObjectState(review, EntityState.Modified);
ctx.SaveChanges();

EDIT: , ReviewNote , ApplyCurrentValues ​​ , , , "":

// This time you don't need to attach:
//ctx.Reviews.Attach(review);
// Make sure you have them in the memory:
Review review2 = (from r in ctx.Reviews.Include("ReviewNotes")
                 where r.ReviewID == reviewID
                 select r).First();
foreach (ReviewNote item in review.ReviewNotes) {
   if (item.ReviewNoteID == 0) {
       ctx.ReviewNotes.AddObject(item);
   }
   else {
       key = ctx.CreateEntityKey("ReviewNotes", item);
       if (ctx.TryGetObjectByKey(key, out original)) {
           // Note that the item is a detached object now: 
           ctx.ApplyCurrentValues(key.EntitySetName, item);
       }
   }
 }
ctx.ObjectStateManager.ChangeObjectState(review, EntityState.Modified);
ctx.SaveChanges();

, ApplyCurrentValues ​​ , Review, , .