TextTrackList.length
The read-only TextTrackList
property length
returns the number of entries in the TextTrackList
, each of which is a TextTrack
representing one track in the media element.
A value of 0 indicates that there are no text tracks in the media.
Syntax
var trackCount = TextTrackList.length;
Value
A number indicating how many text tracks are included in the TextTrackList
. Each track can be accessed by treating the TextTrackList
as an array of objects of type TextTrack
.
Example
This snippet gets the number of text tracks in the first media element found in the DOM by querySelector()
.
var mediaElem = document.querySelector("video, audio"); var numTextTracks = 0; if (mediaElem.textTracks) { numTextTracks = mediaElem.textTracks.length; }
Note that this sample checks to be sure HTMLMediaElement.textTracks
is defined, to avoid failing on browsers without support for TextTrack
.
Specifications
Specification |
---|
HTML Standard (HTML) # dom-texttracklist-length |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
length |
44 |
12 |
31 |
10 |
31 |
6 |
44 |
44 |
31 |
32 |
7 |
4.0 |
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https://developer.mozilla.org/en-US/docs/Web/API/TextTrackList/length