The ignoreCase property indicates whether or not the "i" flag is used with the regular expression. ignoreCase is a read-only property of an individual regular expression instance.

Property attributes of RegExp.prototype.ignoreCase
Writable no
Enumerable no
Configurable yes

Description

The value of ignoreCase is a Boolean and true if the "i" flag was used; otherwise, false. The "i" flag indicates that case should be ignored while attempting a match in a string.

You cannot change this property directly.

Examples

Using ignoreCase

var regex = new RegExp('foo', 'i');

console.log(regex.ignoreCase); // true

Specifications

Specification Status Comment
ECMAScript 3rd Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.2. JavaScript 1.5: ignoreCase is a property of a RegExp instance, not the RegExp object.
ECMAScript 5.1 (ECMA-262)
The definition of 'RegExp.prototype.ignoreCase' in that specification.
Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'RegExp.prototype.ignoreCase' in that specification.
Standard ignoreCase is now a prototype accessor property rather than an instance's own data property.
ECMAScript Latest Draft (ECMA-262)
The definition of 'RegExp.prototype.ignoreCase' in that specification.
Draft  

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
Basic supportChrome Full support YesEdge Full support YesFirefox Full support 1IE Full support YesOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes
Prototype accessor property (ES2015)Chrome Full support YesEdge ? Firefox Full support 38IE ? Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile ? Firefox Android Full support 38Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See also

Document Tags and Contributors

Last updated by: wbamberg,