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    test Redirect 3

    Summary

    The test() method executes a search for a match between a regular expression and a specified string. Returns true or false.

    Syntax

    regexObj.test(str)

    Parameters

    str
    The string against which to match the regular expression.

    Return value

    Boolean. true or false.

    Description

    Use test() whenever you want to know whether a pattern is found in a string (similar to the String.search method); for more information (but slower execution) use the exec method (similar to the String.match method). As with exec (or in combination with it), test called multiple times on the same global regular expression instance will advance past the previous match.

    Examples

    Example: Using test

    The following example prints a message which depends on the success of the test:

    function testinput(re, str){
        var midstring;
        if (re.test(str)) {
            midstring = " contains ";
        } else {
            midstring = " does not contain ";
        }
        console.log(str + midstring + re.source);
    }
    

    Specifications

    Specification Status Comment
    ECMAScript 3rd Edition. Implemented in JavaScript 1.2 Standard Initial definition.
    ECMAScript Language Specification 5.1th Edition (ECMA-262) Standard  
    ECMAScript Language Specification 6th Edition (ECMA-262) Draft  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

    Gecko-specific notes

    Prior to Gecko 8.0 (Firefox 8.0 / Thunderbird 8.0 / SeaMonkey 2.5), test() was implemented incorrectly; when it was called with no parameters, it would match against the value of the previous input (RegExp.input property) instead of against the string "undefined". This is fixed; now /undefined/.test() correctly results in true, instead of an error.

    See also

    Document Tags and Contributors

    Contributors to this page: Sheppy
    Last updated by: Sheppy,