Android 判断当前网络状态

//判断网络连接是否可用
public static boolean isNetworkAvailable(Context context) {   
        ConnectivityManager cm = (ConnectivityManager) context   
                .getSystemService(Context.CONNECTIVITY_SERVICE);   
        if (cm == null) {   
        } else {
　　　　　　　//如果仅仅是用来判断网络连接
　　　　　　  //则可以使用 cm.getActiveNetworkInfo().isAvailable();  
            NetworkInfo[] info = cm.getAllNetworkInfo();   
            if (info != null) {   
                for (int i = 0; i < info.length; i++) {   
                    if (info[i].getState() == NetworkInfo.State.CONNECTED) {   
                        return true;   
                    }   
                }   
            }   
        }   
        return false;   
    }
//判断GPS是否打开
public static boolean isGpsEnabled(Context context) {   
        LocationManager lm = ((LocationManager) context   
                .getSystemService(Context.LOCATION_SERVICE));   
        List<String> accessibleProviders = lm.getProviders(true);   
        return accessibleProviders != null && accessibleProviders.size() > 0;   
    } 


//判断WIFI是否打开
public static boolean isWifiEnabled(Context context) {   
        ConnectivityManager mgrConn = (ConnectivityManager) context   
                .getSystemService(Context.CONNECTIVITY_SERVICE);   
        TelephonyManager mgrTel = (TelephonyManager) context   
                .getSystemService(Context.TELEPHONY_SERVICE);   
        return ((mgrConn.getActiveNetworkInfo() != null && mgrConn   
                .getActiveNetworkInfo().getState() == NetworkInfo.State.CONNECTED) || mgrTel   
                .getNetworkType() == TelephonyManager.NETWORK_TYPE_UMTS);   
    } 
//判断是否是3G网络
 public static boolean is3rd(Context context) {   
        ConnectivityManager cm = (ConnectivityManager) context   
                .getSystemService(Context.CONNECTIVITY_SERVICE);   
        NetworkInfo networkINfo = cm.getActiveNetworkInfo();   
        if (networkINfo != null   
                && networkINfo.getType() == ConnectivityManager.TYPE_MOBILE) {   
            return true;   
        }   
        return false;   
    }  
//判断是wifi还是3g网络,用户的体现性在这里了，wifi就可以建议下载或者在线播放。
 public static boolean isWifi(Context context) {   
            ConnectivityManager cm = (ConnectivityManager) context   
                    .getSystemService(Context.CONNECTIVITY_SERVICE);   
            NetworkInfo networkINfo = cm.getActiveNetworkInfo();   
            if (networkINfo != null   
                    && networkINfo.getType() == ConnectivityManager.TYPE_WIFI) {   
                return true;   
            }   
            return false;   
        }




转：http://www.cnblogs.com/codeworker/archive/2012/04/23/2467180.html