JS: Regex Find/Replace

By Xah Lee. Date: . Last updated: .

Regex means Regular Expression. It is used to check if a string contains certain pattern, or extract the pattern, or replace it with other string. For example, extract email addresses in a text file.

For basic tutorial, see JS: RegExp Tutorial

There are 2 ways to use RegExp in JavaScript:

Following is a summary of the different methods.



Get the index of first char of matched string.

[see JS: String.prototype.search]


Get a array of captured groups, or, get array of all occurrences.

[see JS: String.prototype.match]



Get a new string.

[see JS: String.prototype.replace]



Return true or false.

[JS: RegExp.prototype.test]



Return a array of captured groups.

[JS: RegExp.prototype.exec]

RegExp Topic

  1. JS: RegExp Tutorial
  2. JS: RegExp Syntax
  3. JS: Regex Find/Replace
  4. JS: RegExp Object
  5. JS: RegExp Constructor
  6. JS: RegExp.prototype

String Topic

  1. JS: String Overview
  2. JS: Template String
  3. JS: String Escape Sequence
  4. JS: Unicode Escape Sequence
  5. JS: String Object
  6. JS: String.prototype
  7. JS: String to Number
  8. JS: Encode URL, Escape String
  9. JS: Format Number
  10. JS: JSON
  11. JS: Source Code Encoding
  12. JS: Allowed Characters in Identifier
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