Web/JavaScript/Reference/Global objects/TypedArray/forEach

The forEach() method executes a provided function once per array element. This method has the same algorithm as Array.prototype.forEach(). TypedArray is one of the typed array types here.

Syntax

typedarray.forEach(callback[, thisArg])

Parameters

callback: Function that produces an element of the new typed array, taking three arguments:

currentValue The current element being processed in the typed array. index The index of the current element being processed in the array. array The array forEach() was called upon.

thisArg Optional: Value to use as this when executing callback.

Return value

undefined.

Description

The forEach() method executes the provided callback once for each element present in the typed array in ascending order. It is not invoked for indexes that have been deleted or elided. However, it is executed for elements that are present and have the value undefined.

callback is invoked with three arguments:

the element value
the element index
the typed array being traversed

If a thisArg parameter is provided to forEach(), it will be passed to callback when invoked, for use as its this value. Otherwise, the value undefined will be passed for use as its this value. The this value ultimately observable by callback is determined according to the usual rules for determining the this seen by a function.

The range of elements processed by forEach() is set before the first invocation of callback. Elements that are appended to the typed array after the call to forEach() begins will not be visited by callback . If the values of existing elements of the typed array are changed, the value passed to callback will be the value at the time forEach() visits them; elements that are deleted before being visited are not visited.

forEach() executes the callback function once for each typed array element; unlike every() and some() it, always returns the value undefined.

Examples

Logging the contents of a typed array

The following code logs a line for each element in a typed array:

function logArrayElements(element, index, array) {
  console.log('a[' + index + '] = ' + element);
}

new Uint8Array([0, 1, 2, 3]).forEach(logArrayElements);
// logs:
// a[0] = 0
// a[1] = 1
// a[2] = 2
// a[3] = 3

Specifications

Specification
[(ECMA-262)The definition of '%TypedArray%.prototype.forEach' in that specification.]

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
`forEach`	Chrome Full support 45	Edge Full support 14	Firefox Full support 38	IE No support No	Opera Full support 32	Safari Full support 10	WebView Android Full support 45	Chrome Android Full support 45	Firefox Android Full support 38	Opera Android Full support 32	Safari iOS Full support 10	Samsung Internet Android Full support 5.0	nodejs Full support 4.0.0

Legend

Full support: Full support
No support: No support