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web api instance method

DOMTokenList: forEach() method

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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 classList. We when retrieve an iterator containing the values using forEach(), writing each one to the <pre>’s 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

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also