Amoeba.Windows.MulticastMessageEditWindow._tabControl_SelectionChanged C# (CSharp) Method

        private void _tabControl_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (_tabControl.SelectedItem == _previewTabItem)
            {
                if (string.IsNullOrWhiteSpace(_commentTextBox.Text))
                {
                    _textEditor.Document.Text = "";
                }
                else
                {
                    var digitalSignature = _signatureComboBox.SelectedItem as DigitalSignature;

                    var comment = _commentTextBox.Text.Substring(0, Math.Min(_commentTextBox.Text.Length, Message.MaxCommentLength));
                    _textEditor_Helper.Set(_textEditor, DateTime.UtcNow, digitalSignature.ToString(), 0, comment);
                }
            }
        }