DOMTokenList: forEach() method

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

forEach(callback)
forEach(callback, thisArg)

Parameters

callback

The 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.

thisArg Optional

The value to use as this when executing callback.

Return value

None.

Example

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

HTML

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

JavaScript

const pre = document.querySelector("pre");
const classes = pre.classList;
const iterator = classes.values();

classes.forEach(function (value, key, listObj) {
  pre.textContent += `(${value} ${key})/${this}\n`;
}, "arg");

Result

Specifications

Browser compatibility

See also

• DOMTokenList.entries(), DOMTokenList.keys and DOMTokenList.values.