/** * 判斷當前是否有網絡連接,但是如果該連接的網絡無法上網，也會返回true * @param mContext * @return */ public static boolean isNetConnection(Context mContext) { if (mContext!=null){  ConnectivityManager connectivityManager = (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE);  NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();  boolean connected = networkInfo.isConnected();  if (networkInfo!=null&&connected){   if (networkInfo.getState()== NetworkInfo.State.CONNECTED){    return true;   }else{    return false;   }  } } return false;}

/** * 在子線程里開啟該方法，可檢測當前網絡是否能打開網頁 * true是可以上網，false是不能上網 *  */public static boolean isOnline(){ URL url; try {  url = new URL("https://www.baidu.com");  InputStream stream = url.openStream();  return true; } catch (MalformedURLException e) {  e.printStackTrace(); } catch (IOException e) {  e.printStackTrace(); } return false;}