The RegExp.$+ property represents the last parenthesized substring pattern match.
This is the same as using the lastParen property.
<html> <body> <script language="JavaScript"> <!-- exp = new RegExp("(is)", "g"); str = "This is a test (is)!"; myArray = exp.exec(str); document.write("The RegExp.lastParen is: " + "<b>"+ RegExp.lastParen + "</b>"); --> </script> </body> </html>