CK.WordPredictor.UI.Helpers.TextBoxHelpers.SelectedTextChanged C# (CSharp) Method

        private static void SelectedTextChanged( DependencyObject obj, DependencyPropertyChangedEventArgs e )
        {
            TextBox tb = obj as TextBox;
            if( tb != null )
            {
                if( e.OldValue == null && e.NewValue != null )
                {
                    tb.SelectionChanged += tb_SelectionChanged;
                }
                else if( e.OldValue != null && e.NewValue == null )
                {
                    tb.SelectionChanged -= tb_SelectionChanged;
                }

                string newValue = e.NewValue as string;

                if( newValue != null && newValue != tb.SelectedText )
                {
                    tb.SelectedText = newValue as string;
                }
            }
        }