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    The join() method joins all elements of an array into a string.


    str = arr.join([separator = ','])


    Optional. Specifies a string to separate each element of the array. The separator is converted to a string if necessary. If omitted, the array elements are separated with a comma. If separator is an empty string all ellements are joined without any characters in between them.


    The string conversions of all array elements are joined into one string.


    Example: Joining an array four different ways

    The following example creates an array, a, with three elements, then joins the array four times: using the default separator, then a comma and a space, then a plus and an empty string.

    var a = ['Wind', 'Rain', 'Fire'];
    var myVar1 = a.join();      // assigns 'Wind,Rain,Fire' to myVar1
    var myVar2 = a.join(', ');  // assigns 'Wind, Rain, Fire' to myVar2
    var myVar3 = a.join(' + '); // assigns 'Wind + Rain + Fire' to myVar3
    var myVar4 = a.join('');    // assigns 'WindRainFire' to myVar4


    Specification Status Comment
    ECMAScript 1st Edition Standard Initial definition. Implemented in JavaScript 1.1.
    ECMAScript 5.1 (ECMA-262)
    The definition of 'Array.prototype.join' in that specification.
    ECMAScript 6 (ECMA-262)
    The definition of 'Array.prototype.join' in that specification.
    Release Candidate  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support 1.0 1.0 (1.7 or earlier) 5.5 (Yes) (Yes)
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

    See also

    Document Tags and Contributors

    Last updated by: sohagrdey,
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