The filter()
method creates a new typed array with all elements that pass the test implemented by the provided function. This method has the same algorithm as Array.prototype.filter()
. TypedArray is one of the typed array types here.
typedarray.filter(callback[, thisArg])
callback
(element, index, typedarray)
. Return true
to keep the element, false
otherwise.thisArg Optional
this
when executing callback
.A new typed array with the elements that pass the test.
The filter()
method calls a provided callback
function once for each element in a typed array, and constructs a new typed array of all the values for which callback
returns a true value. callback
is invoked only for indexes of the typed array which have assigned values; it is not invoked for indexes which have been deleted or which have never been assigned values. Typed array elements which do not pass the callback
test are simply skipped, and are not included in the new typed array.
callback
is invoked with three arguments:
If a thisArg
parameter is provided to filter
, 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.
filter()
does not mutate the typed array on which it is called.
The range of elements processed by filter()
is set before the first invocation of callback
. Elements which are appended to the typed array after the call to filter()
begins will not be visited by callback
. If existing elements of the typed array are changed, or deleted, their value as passed to callback
will be the value at the time filter()
visits them; elements that are deleted are not visited.
The following example uses filter()
to create a filtered typed array that has all elements with values less than 10 removed.
function isBigEnough(element, index, array) { return element >= 10; } new Uint8Array([12, 5, 8, 130, 44]).filter(isBigEnough); // Uint8Array [ 12, 130, 44 ]
Arrow functions provide a shorter syntax for the same test.
new Uint8Array([12, 5, 8, 130, 44]).filter(elem => elem >= 10); // Uint8Array [ 12, 130, 44 ]
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'TypedArray.prototype.filter' in that specification. | Standard | Initial definition. |
ECMAScript 2017 Draft (ECMA-262) The definition of 'TypedArray.prototype.filter' in that specification. | Draft |
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 45 | 38 (38) | No support | No support | No support |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | No support | 38.0 (38) | No support | No support | No support |
© 2005–2017 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/JavaScript/Reference/Global_Objects/TypedArray/filter