DbUpdateException was unhandled?

Question

Hi so keep encountering this exception every time when savechanges() is called. There is an other post that has multiple answers but, I cannot pin point which answer is suitable for my problem. Also it seems that everyone has a different opinion about this exception.

Link to other post: [a link] Entity Framework: "Store update, insert, or delete statement affected an unexpected number of rows (0)."

My Exception:

An unhandled exception of type 'System.Data.Entity.Infrastructure.DbUpdateException' occurred in EntityFramework.dll

Additional information: An error occurred while updating the entries. See the inner exception for details.

I am trying to save mails into my storage. I am using entity framework 6.1.3 and SQL server 2014.

This is my method that stores mails:

public int StoreMail(PhishingMail PhishingMail)
{
    using (var phishingMailStorage = new PhishFinderDBModel())
    {
        try
        {
            //// var manager = ((IObjectContextAdapter)phishingMailStorage).ObjectContext.ObjectStateManager;
            //// phishingMailStorage.PhishingMail.Attach(PhishingMail);
            phishingMailStorage.Entry(PhishingMail).State = PhishingMail.PhishingMailId == 0 ? EntityState.Added : EntityState.Modified;
            phishingMailStorage.SaveChanges();

            //// manager.ChangeObjectState(PhishingMail, EntityState.Modified);
            //// phishingMailStorage.SaveChanges();

            Console.WriteLine("Het is gelukt");
        }
        catch (OptimisticConcurrencyException)
        {
            var ctx = ((IObjectContextAdapter)phishingMailStorage).ObjectContext;

            ctx.Refresh(RefreshMode.ClientWins, phishingMailStorage.PhishingMail);
            phishingMailStorage.SaveChanges();
        }
    }

    return PhishingMail.PhishingMailId;
}

This is my get mails method, that does work:

public List<PhishingMail> GetEmails()
{
    phishingMailList = new List<PhishingMail>();
    FolderId InboxId = new FolderId(WellKnownFolderName.Inbox, "******@******.nl");
    FindItemsResults<Item> findResults = service.FindItems(InboxId, new ItemView(20));

    foreach (Item phishingmail in findResults.Items)
    {
        if (!((EmailMessage)phishingmail).IsRead)
        {
             /// ((EmailMessage)phishingmail).IsRead = true;
             ((EmailMessage)phishingmail).Update(ConflictResolutionMode.AutoResolve);
        }

        PhishingMail mail = MailMapper.Map((EmailMessage)phishingmail);

        //// ((EmailMessage)phishingmail).Load(new PropertySet(BasePropertySet.IdOnly, EmailMessageSchema.IsRead));
        phishingMailList.Add(mail);

        /// Console.WriteLine(mail.Type);
    }

    return phishingMailList;
}

Why does savechanges() not work and how do I make it work?

Thank you.

Which line generates the exception and what is in inner exception? — Ivan Stoev, Nov 26 '15 at 12:20
looks like you might want to catch the `DbUpdateException` and view the exception details to figure out what is going wrong. — user1666620, Nov 26 '15 at 12:28

score 0 · Answer 1 · answered Nov 26 '15 at 13:10

write your db.SaveChanges(); method inside a try block. It will tell you the exact problem

try
{
     db.SaveChanges();
}
catch (System.Data.Entity.Validation.DbEntityValidationException dbEx)
{
     Exception raise = dbEx;
     foreach (var validationErrors in dbEx.EntityValidationErrors)
     {
         foreach (var validationError in validationErrors.ValidationErrors)
         {
              string message = string.Format("{0}:{1}",
              validationErrors.Entry.Entity.ToString(),
              validationError.ErrorMessage);

              raise = new InvalidOperationException(message, raise);
         }
      }
      throw raise;
}

DbUpdateException was unhandled?

1 Answers1