Array.unobserve()
Obsolete
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
The Array.unobserve() method was used to remove observers set by Array.observe()
, but has been deprecated and removed from Browsers. You can use the more general Proxy
object instead.
Syntax
Array.unobserve(<var>arr</var>, <var>callback</var>)
Parameters
arr
- The array to stop observing.
callback
- The reference to the observer to stop calling each time changes are made on the array arr.
Description
Array.unobserve()
should be called after Array.observe()
in order to remove an observer from an array.
The callback should be a reference to a function and not an anonymous function, because this reference will be used to unset the previous observer. It's useless to call Array.unobserve() with an anonymous function as callback, it will not remove any observer.
Examples
Unobserving an array
var arr = [1, 2, 3]; var observer = function(changes) { console.log(changes); } Array.observe(arr, observer); arr.push(4); // [{type: "splice", object: <arr>, index: 3, removed:[], addedCount: 1}] Array.unobserve(arr, observer); arr.pop(); // The callback wasn't called
Using an anonymous function
var persons = ['Khalid', 'Ahmed', 'Mohammed']; Array.observe(persons, function (changes) { console.log(changes); }); persons.shift(); // [{type: "splice", object: <arr>, index: 0, removed: [ "Khalid" ], addedCount: 0 }] Array.unobserve(persons, function (changes) { console.log(changes); }); persons.push('Abdullah'); // [{type: "splice", object: <arr>, index: 2, removed: [], addedCount: 1 }] // The callback will always be called
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 36 [1] | No support | No support | 23 | No support |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | 36 [1] | No support | No support | 23 | No support |
[1] Deprecated in Chrome 49.
See also
License
© 2016 Mozilla 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/array/unobserve