JavaScript regular expressions methods

In the following table, you can find the methods used to match or test a regular expression. The main JavaScript objects used in regular expressions are String and RegExp, which represent a pattern (such as regular expression).

Method	Description	Example
String.match(regular expression)	This executes a search for a match within a string, based on a regular expression.	var myString = "today is 12-12-2000"; var matches = myString.match(/\d{4}/); //returns array ["2000"]
RegExp.exec(string)	This executes a search for a match in its string parameter. Unlike String.match, the parameter entered should be a string, not a regular expression pattern.	var pattern = /\d{4}/; pattern.exec("today is 12-12-2000"); //returns array ["2000"]
String.replace(regular expression, replacement text)	This searches and replaces the regular expression portion (match) with the replaced text instead.	var phone = "[phone]"; var phoneFormatted = phone.replace(/[\(\)-\s]/g, ""); //returns 2011234567 (removed ( ) - and blank space)
String.split (string literal or regular expression)	This breaks up a string into an array of substrings, based on a regular expression or fixed string.	var oldstring = "1,2, 3, 4, 5"; var newstring = oldstring.split(/\s*,\s*/); //returns the array ["1","2","3","4","5"]
String.search(regular expression)	This tests for a match in a string. It returns the index of the match, or -1, if it's not found.	var myString = "today is 12-12-2000"; myString.search(/\d{4}/); //returns 15 - index of 2000
RegExp.test(string)	This tests whether the given string matches the Regexp, and returns true if it's matching, and false, if not.	var pattern = /\d{4}/; pattern.test("today is 12-12-2000"); //returns true

In this appendix, we very briefly covered the patterns learned throughout this book in a format that is easy to consult on a day-to-day basis.