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MediaElement.NaturalDuration Property
Silverlight
Gets the duration of the media file currently opened.
Namespace: System.Windows.Controls
Assembly: System.Windows (in System.Windows.dll)
Property Value
Type: System.Windows.DurationThe natural duration of the media. The default value is Automatic, which is the value held if you query this property before MediaOpened.
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.
Once you have the Duration, you can get the specific time from the Duration.TimeSpan property value, calling TimeSpan members such as Seconds, etc.
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.