Gets the duration of the media file currently opened.
Assembly: System.Windows (in System.Windows.dll)
Dependency property identifier field: NaturalDurationProperty
The property value is not available until the MediaOpened event has been raised.
If the opened media is live streaming media that does not have a known duration, this property returns Automatic.
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.