AudioContext
接口的suspend()
方法suspends the progression of time in the audio context, temporarily halting audio hardware access and reducing CPU/battery usage in the process — this is useful if you want an application to power down the audio hardware when it will not be using an audio context for a while.
This method will cause an INVALID_STATE_ERR
exception to be thrown if called on an OfflineAudioContext
.
Syntax
var audioCtx = new AudioContext(); audioCtx.suspend().then(function() { ... });
Returns
A Promise
that resolves with void. The promise is rejected if the context has already been closed.
Example
The following snippet is taken from our AudioContext states demo (see it running live.) When the suspend/resume button is clicked, the AudioContext.state
is queried — if it is running
, suspend()
is called; if it is suspended
, resume
is called. In each case, the text label of the button is updated as appropriate once the promise resolves.
susresBtn.onclick = function() { if(audioCtx.state === 'running') { audioCtx.suspend().then(function() { susresBtn.textContent = 'Resume context'; }); } else if(audioCtx.state === 'suspended') { audioCtx.resume().then(function() { susresBtn.textContent = 'Suspend context'; }); } }
Specifications
Specification | Status | Comment |
---|---|---|
Web Audio API close() |
Working Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | 41.0 | 40.0 (40.0) | 未实现 | ? | ? |
Feature | Android | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|
Basic support | ? | ? | ? | ? | ? | ? | 41.0 |