System.Waf.Presentation.ValidationTracker.ErrorChangedHandler C# (CSharp) Метод

        private void ErrorChangedHandler(object sender, ValidationErrorEventArgs e)
        {
            if (e.Action == ValidationErrorEventAction.Added)
            {
                AddError(e.OriginalSource, e.Error);
            }
            else
            {
                Tuple<object, ValidationError> error = errors.FirstOrDefault(err => err.Item1 == e.OriginalSource && err.Item2 == e.Error);
                if (error != null) { errors.Remove(error); }
            }

            ValidationHelper.InternalSetIsValid(owner, !errors.Any());
        }