private void FillSelectionSpaces(object sender, EventArgs ea)
        {
            string text = GetRegexText();

            text = text.Replace(" ", @"\s");
            text = text.Replace("\t", @"\t");
            text = text.Replace("\n", @"\n");

            text = text.Replace("[", @"\[");
            text = text.Replace("]", @"\]");

            text = text.Replace("(", @"\(");
            text = text.Replace(")", @"\)");

            text = text.Replace("#", @"\#");
            text = text.Replace(".", @"\.");
            text = text.Replace("*", @"\*");
            text = text.Replace("!", @"\!");
            text = text.Replace(":", @"\:");
            text = text.Replace("+", @"\+");
            text = text.Replace("?", @"\?");


            if (txtRegex.SelectedText.Length > 0)
            {
                txtRegex.ReplaceSelection(text);
            }
            else
            {
                txtRegex.Text = text;
            }
        }