This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The signal
read-only property of the AbortController
interface returns an AbortSignal
object instance, which can be used to communicate with/abort a DOM request as desired.
Syntax
var signal = abortController.signal;
Value
An AbortSignal
object instance.
Examples
In the following snippet, we aim to download a video using the Fetch API.
We first create a controller using the AbortController()
constructor, then grab a reference to its associated AbortSignal
object using the AbortController.signal
property.
When the fetch request is initiated, we pass in the AbortSignal
as an option inside the request's options object (see {signal}
, below). This associates the signal and controller with the fetch request and allows us to abort it by calling AbortController.abort()
, as seen below in the second event listener.
var controller = new AbortController(); var signal = controller.signal; var downloadBtn = document.querySelector('.download'); var abortBtn = document.querySelector('.abort'); downloadBtn.addEventListener('click', fetchVideo); abortBtn.addEventListener('click', function() { controller.abort(); console.log('Download aborted'); }); function fetchVideo() { ... fetch(url, {signal}).then(function(response) { ... }).catch(function(e) { reports.textContent = 'Download error: ' + e.message; }) }
Note: When abort()
is called, the fetch()
promise rejects with an AbortError
.
You can find a full working example on GitHub — see abort-api (see it running live also).
Specifications
Specification | Status | Comment |
---|---|---|
DOM The definition of 'signal' in that specification. |
Living Standard | Initial definition |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
signal | Chrome Full support 66 | Edge Full support 16 | Firefox Full support 57 | IE No support No | Opera Full support 53 | Safari
Full support
12.1
| WebView Android Full support 66 | Chrome Android Full support 66 | Firefox Android Full support 57 | Opera Android Full support 47 | Safari iOS
Full support
12.2
| Samsung Internet Android Full support 9.0 |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- See implementation notes.
- See implementation notes.