How to load multiple related entities in DbUpdateConcurrencyException RSS

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  GauravRajput

  Member

  6 Points

  15 Posts

  Re: How to load multiple related entities in DbUpdateConcurrencyException

  Nov 04, 2012 04:50 AM|LINK

  Thanks @ToughMan but unfortunately it does not work, its not that straightforward. Can you give me an example on how it would work?

  
  
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  Decker Dong ...

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  18779 Posts

  Re: How to load multiple related entities in DbUpdateConcurrencyException

  Nov 04, 2012 05:34 AM|LINK

  GauravRajput

  Thanks @ToughMan but unfortunately it does not work, its not that straightforward. Can you give me an example on how it would work?

  [HttpPost]
  public ActionResult Edit(Department department)
  {
      try
      {
          if (ModelState.IsValid)
          {
              db.Entry(department).State = EntityState.Modified;
              db.SaveChanges();
              return RedirectToAction("Index");
          }
      }
      catch (DbUpdateConcurrencyException ex)
      {
          var entry = ex.Entries.Single();
          var databaseValues = (Department)entry.GetDatabaseValues().ToObject();
          var clientValues = (Department)entry.Entity;
          if (databaseValues.Name != clientValues.Name)
              ModelState.AddModelError("Name", "Current value: "
                  + databaseValues.Name);
          if (databaseValues.Budget != clientValues.Budget)
              ModelState.AddModelError("Budget", "Current value: "
                  + String.Format("{0:c}", databaseValues.Budget));
          if (databaseValues.StartDate != clientValues.StartDate)
              ModelState.AddModelError("StartDate", "Current value: "
                  + String.Format("{0:d}", databaseValues.StartDate));
          if (databaseValues.InstructorID != clientValues.InstructorID)
              ModelState.AddModelError("InstructorID", "Current value: "
                  + db.Instructors.Find(databaseValues.InstructorID).FullName);
          ModelState.AddModelError(string.Empty, "The record you attempted to edit "
              + "was modified by another user after you got the original value. The "
              + "edit operation was canceled and the current values in the database "
              + "have been displayed. If you still want to edit this record, click "
              + "the Save button again. Otherwise click the Back to List hyperlink.");
          department.Timestamp = databaseValues.Timestamp;
      }
      catch (DataException)
      {
          //Log the error (add a variable name after Exception)
          ModelState.AddModelError(string.Empty, "Unable to save changes. Try again, and if the problem persists contact your system administrator.");
      }
  
      ViewBag.InstructorID = new SelectList(db.Instructors, "InstructorID", "FullName", department.InstructorID);
      return View(department);
  }

  http://www.asp.net/mvc/tutorials/getting-started-with-ef-using-mvc/handling-concurrency-with-the-entity-framework-in-an-asp-net-mvc-application
  
  

• • Reply
  

  GauravRajput

  Member

  6 Points

  15 Posts

  Re: How to load multiple related entities in DbUpdateConcurrencyException

  Nov 04, 2012 06:06 AM|LINK

  Thanks a lot Decker for your reply, this I have already done beacuse person entity is working for database and client values.

  The issues that was and which stays is why should i load the related entity separately for databasevalues using Find. In your example if department has a foreign key Department Head coming from a table say people, I should be able to refer to People entity for department head when doing

  var databaseValues = (Department)entry.GetDatabaseValues().ToObject();
  

  databasevalues.people.departmenhead, this gives null

  I really appreciate you are taking out time to reply on this query. 

  The solution given by @toughman works as a workaround using find method. Thanks @toughman for refering me to the link.

  Thanks All.

  
  
  • Marked as answer by decker dong - msft on Nov 09, 2012 05:18 AM
• • Reply
  

  Cathy Mi - M...

  Member

  741 Points

  165 Posts

  Microsoft

  Re: How to load multiple related entities in DbUpdateConcurrencyException

  Nov 21, 2012 07:46 PM|LINK

  Hi,

  Were you able to work this out?

  If you cannot determine your answer here or on your own, consider opening a support case with us. Visit this link to see the various support options that are available to better meet your needs:  http://support.microsoft.com/default.aspx?id=fh;en-us;offerprophone.

  Thanks,

  Cathy Miller

• • Reply
  

  Decker Dong ...

  All-Star

  118619 Points

  18779 Posts

  Re: How to load multiple related entities in DbUpdateConcurrencyException

  Nov 30, 2012 12:29 AM|LINK

  Cathy Mi - MSFT

  Cathy Mi - MSFT

  Sorry, I've recently submitted a thread http://forums.asp.net/t/1860461.aspx/2/10?p=True&t=634898176251117433

  But the questioner wanna solved soon.

  He lets me ask the process……:D