How can I access to input data from microphone in Windows Phone 7.0 or 7.1? (like a Volume Meter), i want to detect start and end input data from microphone.
Have a look at How to: Access the Microphone in a Silverlight Application for Windows Phone for basic usage.
If you want to detect the start and stop of certain audio input you'll have to parse/process the returned stream yourself.
This blog post also has a great tutorial (and code) showing how you access the microphone in WP7 via XNA: http://blogs.msdn.com/b/mikeormond/archive/2010/08/27/xna-from-silverlight-on-windows-phone-7-the-microphone.aspx
Good luck!
来源：https://stackoverflow.com/questions/7075278/access-to-input-data-from-microphone-in-wp7