updating in entity framework

[Ahmed Galal]

in my asp.net edit page, i load an entity and its childs from my context and save it in the Application object to preserve it during page postbacks, doing this will make my entity lose its context so i have to reattach it when the user finally click edit. the problem is when i reattach and call SaveChanges and ApplyPropertyChanges only the main entity get updated and not the childs. i have tried to attach the child entities too using AddObject or Attach but i always get exceptions like "An object with a temporary EntityKey value cannot be attached to an object context." OR "An entity object cannot be referenced by multiple instances of IEntityChangeTracker." my code look like this:

        var originalEntity = (from x in verifiersDB.VerificationHosts where x.ID == ID select x).FirstOrDefault();

        originalEntity.VerificationHostSearchs.Load();
        verifiersDB.Attach(originalEntity);

        foreach (var l in verificationHost.VerificationHostSearchs)
            verifiersDB.AddObject("VerificationHostSearchs",l);  //calling AddObject or Attach will throw an exception
        
        verificationHost.Type = short.Parse(ddlHostType.SelectedValue);
        verificationHost.HostName = txtHostName.Text;
        verificationHost.Description = txtHostDescription.Text;
        verificationHost.HostUrl = txtHostURL.Text;

        verifiersDB.ApplyPropertyChanges("VerificationHosts", verificationHost);

        verifiersDB.SaveChanges();

verificationHost is retrieved from the Application state Any help will be appreciated. Thanks in advance.