IAnimationDuration Property

Duration of one animation loop in milliseconds. If duration has not been explicitly set using the SetDuration method, the duration is determined by length of the animation tracks (elements). If duration has been explicitly set, all tracks are temporally scaled to the specified length, so the estimated duration should also equal to the specified one. The duration estimate becomes available (valid) only after animation is started and tracks are finalized.

float Duration { get; }