基于ADNROID 检测网络是否可用的两种方式

 /**
      * 检测网络是否可用1
      * @param act
      * @return
      */
     public boolean isNetConnected(Activity act){

             ConnectivityManager manager = (ConnectivityManager) act
                    .getApplicationContext().getSystemService(
                           Context.CONNECTIVITY_SERVICE);

             if (manager == null) {
                 return false;
             }
             NetworkInfo networkinfo = manager.getActiveNetworkInfo();
             if (networkinfo == null || !networkinfo.isAvailable()) {
                 return false;
             }
             return true;
     }

 /**
      * 检测网络是否可用2
      */
 private boolean isNetConnected() {
         PppoeManager pppoeManager = PppoeManager.getInstance();
         EthernetManager ethernetManager = EthernetManager.getInstance();
         ConnectivityManager connectivityManager = (ConnectivityManager)
      getSystemService(CONNECTIVITY_SERVICE);
         NetworkInfo networkInfo = connectivityManager.getNetworkInfo
     (ConnectivityManager.TYPE_WIFI);
         if (networkInfo.isConnected() || ethernetManager.isNetworkConnected()
                 || pppoeManager.getPppoeStatus().equals
         (PppoeManager.PPPOE_STATE_CONNECT)) {
             return true;
         } else {
             return false;
         }
     }