public virtual void UnMarkAll(string pattern) { try { RegexOptions opt = CaseChecked ? RegexOptions.None : RegexOptions.IgnoreCase;/*match case*/ if (WholeWordChecked) { pattern = "\\b" + pattern + "\\b";/*match all*/ } List <int> lines = tb.FindLines(pattern, opt); foreach (int line in lines) { tb.UnbookmarkLine(line); } } catch (Exception ex) { MessageBox.Show(ex.Message); } }