Unity判断网络连接类型

使用NetworkReachability判断手机游戏当前的网络连接类型，是wifi还是234G

using UnityEngine;
using System.Collections;

public class Test : MonoBehaviour {

    string str;
    // Use this for initialization
    void Start () {
        if (Application.internetReachability == NetworkReachability.ReachableViaCarrierDataNetwork)
        {
            str = "2G/3G/4G";
        }
        else if (Application.internetReachability == NetworkReachability.ReachableViaLocalAreaNetwork)
        {
            str = "wifi";
        }
        else if (Application.internetReachability == NetworkReachability.NotReachable)
        {
            str = "No Network";
        }
        

    }
    
    // Update is called once per frame
    void Update () {
        
    }

    void OnGUI()
    {
        GUILayout.Label(str);
    }
}