Countdown timer for metro App

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C#

Metro-design

VS2012

I tried to make a small game that's need a timer, countdown from 10 to 0. But at this Visual Studio there is no Timer Component, and DispatcherTimer Not mapped to an xmlns.

I Tried to use TimeSpan, that have this field "TicksPerSecond" But this example dosen't help me to make my countdown timer :
http://msdn.microsoft.com/en-us/library/system.timespan.tickspersecond.aspx[^]

TimeSpan also have this method "FromSeconds", and i Can't also use this one for my countdown timer :
http://msdn.microsoft.com/en-us/library/system.timespan.fromseconds.aspx[^]

what can I do for this countdown timer?

[edit] clickable links added [/edit]