// Save changes back to the database and make them permanent
private void saveChanges_Click(object sender, RoutedEventArgs e)
{
try
{
schoolContext.SaveChanges();
saveChanges.IsEnabled = false;
}
// Disse exceptions bliver først gennemgået senere, men det er langhåret. Det binder sig til
// schoolContext, som er databasen.
catch (OptimisticConcurrencyException ex)
{
// If the user has changed the same students earlier, then overwrite their changes with the new data
this.schoolContext.Refresh(RefreshMode.StoreWins, schoolContext.Students);
this.schoolContext.SaveChanges();
}
catch (UpdateException uEx)
{
MessageBox.Show("Error occured when saving changes:\n" + uEx.InnerException.Message
, "Error saving changes");
this.schoolContext.Refresh(RefreshMode.StoreWins, schoolContext.Students);
}
catch (Exception ex)
{
MessageBox.Show("An error occured:\n" + ex.InnerException.Message
, "Error saving changes");
this.schoolContext.Refresh(RefreshMode.StoreWins, schoolContext.Students);
}
}
// Save changes back to the database and make them permanent
private void saveChanges_Click(object sender, RoutedEventArgs e)
{
// TODO: Exercise 3: Task 2b: Save the changes by calling the SaveChanges method of the schoolContext object
// TODO: Exercise 3: Task 3a: If an OptimisticConcurrencyException occurs then another user has changed the same students earlier, then overwrite their changes with the new data (see the lab instructions for details)
// TODO: Exercise 3: Task 3b: If an UpdateException occurs then report the error to the user and rollback (see the lab instructions for details)
// TODO: Exercise 3: Task 3c: If some other sort of error has occurs, report the error to the user and retain the data so the user can try again - the error may be transitory (see the lab instructions for details)
StringBuilder messages = new StringBuilder();
try
{
schoolContext.SaveChanges();
}
catch (OptimisticConcurrencyException ocex)
{
messages.AppendLine("Optimistic concurrency exception");
this.schoolContext.Refresh(RefreshMode.ClientWins, schoolContext);
}
catch (UpdateException updex)
{
messages.AppendLine("Update exception");
this.schoolContext.Refresh(RefreshMode.StoreWins, schoolContext);
}
catch (Exception ex)
{
messages.AppendLine("È successo un Errore");
}
if (messages.Length > 0)
{
MessageBox.Show(messages.ToString());
}
saveChanges.IsEnabled = false;
}
// Save changes back to the database and make them permanent
private void saveChanges_Click(object sender, RoutedEventArgs e)
{
try
{
schoolContext.SaveChanges();
saveChanges.IsEnabled = false;
}
catch (OptimisticConcurrencyException)
{
this.schoolContext.Refresh(RefreshMode.StoreWins, schoolContext.Students);
this.schoolContext.SaveChanges();
}
catch (UpdateException uEx)
{
MessageBox.Show(uEx.InnerException.Message, "Error saving changes");
this.schoolContext.Refresh(RefreshMode.StoreWins, schoolContext.Students);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error saving changes");
this.schoolContext.Refresh(RefreshMode.ClientWins, schoolContext.Students);
}
saveChanges.IsEnabled = false;
// TODO: Exercise 3: Task 2b: Save the changes by calling the SaveChanges method of the schoolContext object
// TODO: Exercise 3: Task 3a: If an OptimisticConcurrencyException occurs then another user has changed the same students earlier, then overwrite their changes with the new data (see the lab instructions for details)
// TODO: Exercise 3: Task 3b: If an UpdateException occurs then report the error to the user and rollback (see the lab instructions for details)
// TODO: Exercise 3: Task 3c: If some other sort of error has occurs, report the error to the user and retain the data so the user can try again - the error may be transitory (see the lab instructions for details)
}
// Save changes back to the database and make them permanent
private void saveChanges_Click(object sender, RoutedEventArgs e)
{
try
{
schoolContext.SaveChanges();
this.saveChanges.IsEnabled = false;
}
catch (OptimisticConcurrencyException exc)
{
this.schoolContext.Refresh(System.Data.Objects.RefreshMode.StoreWins, schoolContext.Students);
this.schoolContext.SaveChanges();
}
catch (UpdateException exc)
{
MessageBox.Show(exc.InnerException.Message, "Error saving changes");
this.schoolContext.Refresh(System.Data.Objects.RefreshMode.StoreWins, schoolContext.Students);
}
catch (Exception exc)
{
MessageBox.Show(exc.Message, "Error saving changes");
this.schoolContext.Refresh(System.Data.Objects.RefreshMode.ClientWins, schoolContext.Students);
}
}
private void saveChanges_Click(object sender, RoutedEventArgs e)
{
schoolContext.SaveChanges();
saveChanges.IsEnabled = false;
}