HTMLAudioElement: Audio() constructor
The Audio()
constructor creates
and returns a new HTMLAudioElement
which can be either attached to
a document for the user to interact with and/or listen to, or can be used
offscreen to manage and play audio.
Syntax
js
new Audio()
new Audio(url)
Parameters
url
Optional-
An optional string containing the URL of an audio file to be associated with the new audio element.
Return value
A new HTMLAudioElement
object, configured to be used for playing back
the audio from the file specified by url
. The new object's
preload
property is set
to auto
and its src
property is set to the specified URL
or null
if no URL is given. If a URL is specified, the browser begins
to asynchronously load the media resource before returning the new object.
Usage notes
You can also use other element-creation methods, such as the document
object's createElement()
method, to construct
a new HTMLAudioElement
.
Determining when playback can begin
There are three ways you can tell when enough of the audio file has loaded to allow playback to begin:
-
Check the value of the
readyState
property. If it'sHTMLMediaElement.HAVE_FUTURE_DATA
, there's enough data available to begin playback and play for at least a short time. If it'sHTMLMediaElement.HAVE_ENOUGH_DATA
, then there's enough data available that, given the current download rate, you should be able to play the audio through to the end without interruption. -
Listen for the
canplay
event. It is sent to the<audio>
element when there's enough audio available to begin playback, although interruptions may occur. -
Listen for the
canplaythrough
event. It is sent when it's estimated that the audio should be able to play to the end without interruption.
The event-based approach is best:
js
myAudioElement.addEventListener("canplaythrough", (event) => {
/* the audio is now playable; play it if permissions allow */
myAudioElement.play();
});
Memory usage and management
If all references to an audio element created using
the Audio()
constructor are deleted, the element itself won't be removed
from memory by the JavaScript runtime's garbage collection mechanism if playback is
currently underway. Instead, the audio will keep playing and the object will remain in
memory until playback ends or is paused (such as by calling
pause()
). At that time, the object becomes
subject to garbage collection.
Specifications
Specification |
---|
HTML Standard # dom-audio-dev |
Browser compatibility
BCD tables only load in the browser
See also
- Web media technologies
- HTML element implementing this interface:
<audio>
.