Android: 網路是否通？

記得在AndroidManifest.xml加上

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE">

public boolean isNetworkAvailable() {
 ConnectivityManager cm=(ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
 NetworkInfo networkInfo = cm.getActiveNetworkInfo();
  // if no network is available networkInfo will be null, otherwise check if we are connected
  if (networkInfo != null && networkInfo.isConnected())
        return true;
  return false;
}