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This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for the proper prefixes to use in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the spec changes.

The TrackDefault() getter method of the TrackDefaultList interface allows the TrackDefault objects in the list to be accessed with an array operator (i.e. [].)


var myTrackDefault = TrackDefaultList[index];


The index position of the TrackDefault object you want to return.


A TrackDefault object.


No specific errors are returned, but if the supplied index is great than or equal to TrackDefaultList.length, the operation will return undefined.




Specification Status Comment
Media Source Extensions
The definition of 'TrackDefault() getter' in that specification.
Candidate Recommendation Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support ? Not supported ? ? ?
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support ?

Not supported

Not supported ? ? Not supported

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills
 Last updated by: chrisdavidmills,