RegExp

You can create a regular expression object using the RegExp() constructor. You pass the expression pattern as the first parameter and the pattern modifiers as the second.

> var re = new RegExp('[dn]o+dle', 'gmi');

This matches "noodle", "doodle", "doooodle", and so on. It's equivalent to using the regular expression literal:

> var re = ('/[dn]o+dle/gmi'); // recommended

Chapter 4, Objects and Appendix D, Regular Expressions contains more information on regular expressions and patterns.

The RegExp.prototype members

Property/method	Description
global	Read-only. true if the g modifier was set when creating the regexp object.
ignoreCase	Read-only. true if the i modifier was set when creating the regexp object.
multiline	Read-only. true if the m modifier was set when creating the regexp object
lastIndex	Contains the position in the string where the next match should start. test() and exec() set this...