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    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


    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.


    Example: Using ignoreCase

    var regex = new RegExp('foo', 'i');
    console.log(regex.ignoreCase); // true


    Specification Status Comment
    ECMAScript 3rd Edition. 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.
    ECMAScript 6 (ECMA-262)
    The definition of 'RegExp.prototype.ignoreCase' in that specification.
    Draft ignoreCase is now a prototype accessor property rather than an instance's own data property.

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
    Prototype accessor property ? 38 (38) ? ? ?
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
    Prototype accessor property ? ? 38.0 (38) ? ? ?

    See also

    Document Tags and Contributors

    Contributors to this page: Sheppy, fscholz, Mingun, Prodoc, Mgjbot, Maian, Dria
    Last updated by: fscholz,