Question

I try to save an edited Entity Framework entity ApplyPropertyChanges, and get an exception:

“The ObjectStateManager does not
contain an ObjectStateEntry with a
reference to an object of type
‘MvcApplication1.Models.Product’.”} System.Exception
{System.InvalidOperationException}

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(Product productToEdit) //all properties of Product are valid
 {
                try
                {
productsDBEntities.ApplyPropertyChanges("ProductSet", productToEdit); //exception here
                    entities.SaveChanges();
                    return RedirectToAction("Index");
                }
                catch
                {
                    return View();
                }
            }

Any idea would be very much appreciated!

Thanks!

Answer 1

You must first load Product from database if you want to use ApplyPropertyChanges:

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(Product productToEdit) 
{
    try
    {
        entities.Products.Single(p => p.Id == productToEdit.Id);
        entities.ApplyPropertyChanges("ProductSet", productToEdit);
        entities.SaveChanges();
        return RedirectToAction("Index");
    }
    catch
    {
        return View();
    }
}

Or you can use another approach:

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(Product productToEdit) 
{
    try
    {
        entities.AttachTo("ProductSet", productToEdit);
        entities.ObjectStateManager.GetObjectStateEntry(productToEdit).SetModified();
        entities.SaveChanges();
        return RedirectToAction("Index");
    }
    catch
    {
        return View();
    }
}

Btw. are you using .NET 3.5? ApplyPropertyChanges is obsolete in .NET 4.0.