判断是否连接网络以及是否是局域网

判断是否能上外网
有时候我们连接上一个没有外网连接的WiFi或者需要输入账号和密码才能链接外网的网络，就会出现虽然网络可用，但是外网却不可以访问。针对这种情况，一般的解决办法就是ping一个外网，如果能ping通就说明可以真正上网，代码如下
 
* @author sichard
     * @category 判断是否有外网连接（普通方法不能判断外网的网络是否连接，比如连接上局域网）
     * @return
     */ 
    public static final boolean ping() { 
    
        String result = null; 
        try { 
                String ip = "www.baidu.com";// ping 的地址，可以换成任何一种可靠的外网 
                Process p = Runtime.getRuntime().exec("ping -c 3 -w 100 " + ip);// ping网址3次 
                // 读取ping的内容，可以不加 
                InputStream input = p.getInputStream(); 
                BufferedReader in = new BufferedReader(new InputStreamReader(input)); 
                StringBuffer stringBuffer = new StringBuffer(); 
                String content = ""; 
                while ((content = in.readLine()) != null) { 
                        stringBuffer.append(content); 
                } 
                Log.d("------ping-----", "result content : " + stringBuffer.toString()); 
                // ping的状态 
                int status = p.waitFor(); 
                if (status == 0) { 
                        result = "success"; 
                        return true; 
                } else { 
                        result = "failed"; 
                } 
        } catch (IOException e) { 
                result = "IOException"; 
        } catch (InterruptedException e) { 
                result = "InterruptedException"; 
        } finally { 
                Log.d("----result---", "result = " + result); 
        } 
        return false;
判断能否联网以及判断联网的类型
        
public static String GetNetworkType()
{
    String strNetworkType = "";
    
    NetworkInfo networkInfo = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE).getActiveNetworkInfo();
    if (networkInfo != null && networkInfo.isConnected())
    {
        if (networkInfo.getType() == ConnectivityManager.TYPE_WIFI)
        {
            strNetworkType = "WIFI";
        }
        else if (networkInfo.getType() == ConnectivityManager.TYPE_MOBILE)
        {
            String _strSubTypeName = networkInfo.getSubtypeName();
            
            Log.e("cocos2d-x", "Network getSubtypeName : " + _strSubTypeName);
            
            // TD-SCDMA   networkType is 17
            int networkType = networkInfo.getSubtype();
            switch (networkType) {
                case TelephonyManager.NETWORK_TYPE_GPRS:
                case TelephonyManager.NETWORK_TYPE_EDGE:
                case TelephonyManager.NETWORK_TYPE_CDMA:
                case TelephonyManager.NETWORK_TYPE_1xRTT:
                case TelephonyManager.NETWORK_TYPE_IDEN: //api<8 : replace by 11
                    strNetworkType = "2G";
                    break;
                case TelephonyManager.NETWORK_TYPE_UMTS:
                case TelephonyManager.NETWORK_TYPE_EVDO_0:
                case TelephonyManager.NETWORK_TYPE_EVDO_A:
                case TelephonyManager.NETWORK_TYPE_HSDPA:
                case TelephonyManager.NETWORK_TYPE_HSUPA:
                case TelephonyManager.NETWORK_TYPE_HSPA:
                case TelephonyManager.NETWORK_TYPE_EVDO_B: //api<9 : replace by 14
                case TelephonyManager.NETWORK_TYPE_EHRPD:  //api<11 : replace by 12
                case TelephonyManager.NETWORK_TYPE_HSPAP:  //api<13 : replace by 15
                    strNetworkType = "3G";
                    break;
                case TelephonyManager.NETWORK_TYPE_LTE:    //api<11 : replace by 13
                    strNetworkType = "4G";
                    break;
                default:
                    // http://baike.baidu.com/item/TD-SCDMA 中国移动 联通 电信 三种3G制式
                    if (_strSubTypeName.equalsIgnoreCase("TD-SCDMA") || _strSubTypeName.equalsIgnoreCase("WCDMA") || _strSubTypeName.equalsIgnoreCase("CDMA2000")) 
                    {
                        strNetworkType = "3G";
                    }
                    else
                    {
                        strNetworkType = _strSubTypeName;
                    }
                    
                    break;
             }
             
            Log.e("cocos2d-x", "Network getSubtype : " + Integer.valueOf(networkType).toString());
        }
    }
    
    Log.e("cocos2d-x", "Network Type : " + strNetworkType);
    
    return strNetworkType;
}