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DOMTokenList.forEach

The forEach() method of the DOMTokenList interface calls the callback given in parameter once for each value pair in the list, in insertion order.

Syntax

tokenList.forEach(callback);
tokenList.forEach(callback, argument);

Parameters

callback
Function to execute for each element, eventually taking three arguments:
currentValue
The current element being processed in the array.
currentIndex
The index of the current element being processed in the array.
listObj
The array that forEach() is being applied to.
argument Optional
Value to use as this when executing callback.

Return value

undefined.

Example

In the following example we retrieve the list of classes set on a <span> element as a DOMTokenList using Element.classList. We when retrieve an iterator containing the values using forEach(), writing each one to the <span>'s Node.textContent inside the forEach() inner function.

HTML

<span class="a b c"></span>

JavaScript

var span = document.querySelector("span");
var classes = span.classList;
var iterator = classes.values();

classes.forEach(
  function(value, key, listObj) {
    span.textContent += value + ' ' + key + "/" + this + '  ++  ';
  },
  "arg"
);

Result

Specifications

Specification Status Comment
DOM
The definition of 'forEach() (as iterable<Node>)' in that specification.
Living Standard Initial definition.

Browser CompatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes No 50 ? Yes ?
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes Yes ? 50 Yes ? Yes

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/DOMTokenList/forEach