Android Telephony How to get my telephone number?

Gets the phone number the app is running on. It needs a permission so add the line uses-permission android:name="android.permission.READ_PHONE_STATE" to the manifest.xml 

 private String getMyPhoneNumber(){

   TelephonyManager mTelephonyMgr;

   mTelephonyMgr = (TelephonyManager)

    getSystemService(Context.TELEPHONY_SERVICE);

   return mTelephonyMgr.getLine1Number();

 }

 private String getMy10DigitPhoneNumber(){

  String s = getMyPhoneNumber();

  return s.substring(2);

 }