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I have written a lot of JavaScript code using getElementsByClass name and now realised this is not supported in IE8 so am trying to swap them all for the jQuery equivalent.

My code runs without errors using

   div1.getElementsByClassName("div2");

however if I swap this line for

   $(".div1 .div2");

my code produces an error "Uncaught NotFoundError: An attempt was made to reference a Node in a context where it does not exist."

What is the difference between the JavaScript code and jQuery code that could make the code behave differently?

I have written a lot of JavaScript code using getElementsByClass name and now realised this is not supported in IE8 so am trying to swap them all for the jQuery equivalent.

My code runs without errors using

   div1.getElementsByClassName("div2");

however if I swap this line for

   $(".div1 .div2");

my code produces an error "Uncaught NotFoundError: An attempt was made to reference a Node in a context where it does not exist."

What is the difference between the JavaScript code and jQuery code that could make the code behave differently?

• javascript
• jquery
• getelementsbyclassname

Share Improve this question Follow edited May 18, 2014 at 13:38 BoltClock 725k165165 gold badges1.4k1.4k silver badges1.4k1.4k bronze badges asked Dec 16, 2013 at 17:22 AlexAlex 1,06022 gold badges1717 silver badges3737 bronze badges 7

• 1 Can you replicate it in a fiddle? What you have should work.. – PSL Commented Dec 16, 2013 at 17:23
• 1 Are you using the version of jQuery which does not support IE8? – SLaks Commented Dec 16, 2013 at 17:25
• 2 That error pops up when you try to use native methods on a jQuery object (in certain cases), so the issue isn't the selector, that is correct, it's how you're trying to use it. – adeneo Commented Dec 16, 2013 at 17:25
• 2 Try using $(".div1 .div2").get() and see what happens, or rewrite your script to work with jQuery objects, and not DOM nodes. – adeneo Commented Dec 16, 2013 at 17:29
• I am setting a variable equal to $(".div1 .div2") and trying to reference the second element in the DOM array with x[1] when I get the error – Alex Commented Dec 16, 2013 at 17:42

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2 Answers 2

Sorted by: Reset to default 2

If you've already written code using getElementsByClassName, you might be better off using a shim or polyfill so you don't have to rewrite existing code.

Unfortunately, most of the stuff out there only supplies document.getElementsByClassName, so if you're using it from other elements, you'll have to roll your own you can try this one I wrote a while back.

// getElementsByClassName polyfill
(function(){
    if (document.getElementsByClassName)
        return;
    if (!window.Element)
        throw "Can't polyfill getElementsByClassName";

    function gEBCN(className) {
        var all = this.getElementsByTagName("*"),
            rex = new RegExp("(?:\\s|^)" + className + "(?:\\s|$)"),
            out = [],
            element, i;
        for (i = all.length; i--;) {
            element = all[i];
            if (element.className.match(rex))
                out.unshift(element);
        }
        return out;
    }

    var el = window.Element.prototype;
    var doc = document.constructor.prototype;
    el.getElementsByClassName = doc.getElementsByClassName = gEBCN;
}());

This script checks if document.getElementsByClassName exists, and if it doesn't, it creates document.getElementsByClassName and Element.prototype.getElementsByClassName with equivalent functionality. Since all HTML elements have Element.prototype in their prototype chain, you'll be able to call .getElementsByClassName on any element, just as you can in any browser that has native support for the function. In other words, you can just drop this code at the top of your file or put it a separate file and include it, and then your current scripts should work in old IE and any other browsers that don't support .getElementsByClassName.

Note that jQuery 2.x does not support IE6/7/8. This might be the problem. Instead, use the 1.x branch (for example version [1.10.2]), which still supports those browsers.

When using a 1.x version of jQuery, the following should be the correct selector for what you want.

$(".div1 .div2") //or:
$(".div1").find(".div2") // or, if .div2 is a direct descendant:
$(".div1 > .div2")

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