RegExp.lastParen ($+)

Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The non-standard lastParen property is a static and read-only property of regular expressions that contains the last parenthesized substring match, if any. RegExp.$+ is an alias for this property.

Syntax

RegExp.lastParen
RegExp['$+']

Description

The lastParen property is static, it is not a property of an individual regular expression object. Instead, you always use it as RegExp.lastParen or RegExp['$+'].

The value of the lastParen property is read-only and modified whenever a successful match is made.

You can not use the shorthand alias with the dot property accessor (RegExp.$+), because the parser expects an expression with "+" in that case and a SyntaxError is thrown. Use the bracket notation for property access.

Examples

Using lastParen and $+

var re = /(hi)/g;
re.test('hi there!');
RegExp.lastParen; // "hi"
RegExp['$+'];     // "hi"

Specifications

Non-standard. Not part of any current specification.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
RegExp.lastParen ($+)
Non-standard
Chrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 5.5Opera Full support YesSafari Full support 3WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support 1Samsung Internet Android Full support 1.0nodejs Full support Yes

Legend

Full support  
Full support
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.

See also

Các chủ đề liên quan
  1. Standard built-in objects
  2. RegExp
  3. Properties
    1. RegExp.$1-$9
    2. RegExp.input ($_)
    3. RegExp.lastMatch ($&)
    4. RegExp.lastParen ($+)
    5. RegExp.leftContext ($`)
    6. RegExp.prototype
    7. RegExp.prototype.dotAll
    8. RegExp.prototype.flags
    9. RegExp.prototype.global
    10. RegExp.prototype.ignoreCase
    11. RegExp.prototype.multiline
    12. RegExp.prototype.source
    13. RegExp.prototype.sticky
    14. RegExp.prototype.unicode
    15. RegExp.rightContext ($')
    16. get RegExp[@@species]
    17. regexp.lastIndex
  4. Methods
    1. RegExp.prototype.compile()
    2. RegExp.prototype.exec()
    3. RegExp.prototype.test()
    4. RegExp.prototype.toSource()
    5. RegExp.prototype.toString()
    6. RegExp.prototype[@@matchAll]()
    7. RegExp.prototype[@@match]()
    8. RegExp.prototype[@@replace]()
    9. RegExp.prototype[@@search]()
    10. RegExp.prototype[@@split]()
  5. Inheritance:
  6. Function
  7. Properties
    1. Function.arguments
    2. Function.arity
    3. Function.caller
    4. Function.displayName
    5. Function.length
    6. Function.name
    7. Function.prototype
  8. Methods
    1. Function.prototype.apply()
    2. Function.prototype.bind()
    3. Function.prototype.call()
    4. Function.prototype.isGenerator()
    5. Function.prototype.toSource()
    6. Function.prototype.toString()
  9. Object
  10. Properties
    1. Object.prototype.__count__
    2. Object.prototype.__noSuchMethod__
    3. Object.prototype.__parent__
    4. Object.prototype.__proto__
    5. Object.prototype.constructor
  11. Methods
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.unwatch()
    12. Object.prototype.valueOf()
    13. Object.prototype.watch()
    14. Object.setPrototypeOf()