The enqueue()
method of the ReadableStreamDefaultController
interface enqueues a given chunk in the associated stream.
Syntax
readableStreamDefaultController.enqueue(chunk);
Parameters
- chunk
- The chunk to enqueue.
Return value
undefined
.
Exceptions
- TypeError
- The source object is not a
ReadableStreamDefaultController
.
Examples
In the following simple example, a custom ReadableStream
is created using a constructor (see our Simple random stream example for the full code). The start()
function generates a random string of text every second and enqueues it into the stream — see controller.enqueue(string)
. A cancel()
function is also provided to stop the generation if ReadableStream.cancel()
is called for any reason.
When a button is pressed, the generation is stopped, the stream is closed using ReadableStreamDefaultController.close()
, and another function is run, which reads the data back out of the stream.
const stream = new ReadableStream({ start(controller) { interval = setInterval(() => { let string = randomChars(); // Add the string to the stream controller.enqueue(string); // show it on the screen let listItem = document.createElement('li'); listItem.textContent = string; list1.appendChild(listItem); }, 1000); button.addEventListener('click', function() { clearInterval(interval); fetchStream(); controller.close(); }) }, pull(controller) { // We don't really need a pull in this example }, cancel() { // This is called if the reader cancels, // so we should stop generating strings clearInterval(interval); } });
Specifications
Specification | Status | Comment |
---|---|---|
Streams The definition of 'enqueue()' in that specification. |
Living Standard | Initial definition. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
enqueue | Chrome ? | Edge ? | Firefox
Full support
65
| IE ? | Opera ? | Safari ? | WebView Android ? | Chrome Android ? | Firefox Android
Full support
65
| Opera Android ? | Safari iOS ? | Samsung Internet Android ? |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- User must explicitly enable this feature.
- User must explicitly enable this feature.