The arrayBuffer()
method of the Body
mixin takes a Response
stream and reads it to completion. It returns a promise that resolves with an ArrayBuffer
.
Syntax
response.arrayBuffer().then(function(buffer) { // do something with buffer });
Parameters
None.
Return value
A promise that resolves with an ArrayBuffer
.
Examples
Playing music
In our fetch array buffer live, we have a Play button. When pressed, the getData()
function is run. Note that before playing full audio file will be downloaded. If you need to play ogg during downloading (stream it) - consider HTMLAudioElement
:
new Audio("music.ogg").play();
In getData()
we create a new request using the Request()
constructor, then use it to fetch an OGG music track. We also use AudioContext.createBufferSource
to create an audio buffer source. When the fetch is successful, we read an ArrayBuffer
out of the response using arrayBuffer()
, decode the audio data using AudioContext.decodeAudioData
, set the decoded data as the audio buffer source's buffer (source.buffer
), then connect the source up to the AudioContext.destination
.
Once getData()
has finished running, we start the audio source playing with start(0)
, then disable the play button so it can't be clicked again when it is already playing (this would cause an error.)
function getData() { source = audioCtx.createBufferSource(); var myRequest = new Request('viper.ogg'); fetch(myRequest).then(function(response) { return response.arrayBuffer(); }).then(function(buffer) { audioCtx.decodeAudioData(buffer, function(decodedData) { source.buffer = decodedData; source.connect(audioCtx.destination); }); }); }; // wire up buttons to stop and play audio play.onclick = function() { getData(); source.start(0); play.setAttribute('disabled', 'disabled'); }
Reading files
The Response()
constructor accepts File
s and Blob
s, so it may be used to read a File
into other formats.
function readFile(file) { return new Response(file).arrayBuffer(); }
<input type="file" onchange="readFile(this.files[0])">
Specifications
Specification | Status | Comment |
---|---|---|
Fetch The definition of 'arrayBuffer()' in that specification. |
Living Standard |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
arrayBuffer | Chrome
Full support
42
| Edge Full support ≤18 | Firefox
Full support
39
| IE No support No | Opera
Full support
29
| Safari Full support 10 | WebView Android No support No | Chrome Android Full support 42 | Firefox Android No support No | Opera Android
Full support
29
| Safari iOS Full support Yes | Samsung Internet Android No support No |
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.
- User must explicitly enable this feature.
- User must explicitly enable this feature.