Unity获取GPS地理位置信息

unity获取地理位置

因为项目功能需要，需要获取用户当前的位置信息，百度了一下，很多资料，发现都不能满足直自己的需求。于是整合了网上的资料，才满足自己的需求，说说需求吧：需要定位到玩家具体位置，具体到街道信息。

获取经纬度

获取经纬的方式我使用自带API, 官方说明；http://docs.unity3d.com/Documentation/ScriptReference/LocationService.Start.html
几个重要的参数；

1. isEnabledByUser – 检测用户设置里的定位服务是否启用（首次会弹出提示，询问用户是否同意。如果不同意，定位会失败）
2. lastData – 最近一次测量的地理位置（LocationInfo lastData； 也就是要和 LocationInfo 关联了）
3. status – 定位服务的状态
4. 其他属性，自行看文档，毕竟看官方文档是我们学习知识最好和最快的方式之一，

代码如下

    IEnumerator Start()
    {
        if (!Input.location.isEnabledByUser)
        {
            Input.location.Start();

            yield break;
        }
           
        // Start service before querying location
        Input.location.Start();

        // Wait until service initializes
        int maxWait = 20;
        while (Input.location.status == LocationServiceStatus.Initializing && maxWait > 0)
        {
            yield return new WaitForSeconds(1);
            maxWait--;
        }

        // Service didn't initialize in 20 seconds
        if (maxWait < 1)
        {
            print("Timed out");
            yield break;
        }

        // Connection has failed
        if (Input.location.status == LocationServiceStatus.Failed)
        {
            print("Unable to determine device location");
            yield break;
        }
        else
        {
            // Access granted and location value could be retrieved
            print("Location: " + Input.location.lastData.latitude + " " + Input.location.lastData.longitude + " " + Input.location.lastData.altitude + " " + Input.location.lastData.horizontalAccuracy + " " + Input.location.lastData.timestamp);

            //取出位置的经纬度
            string str = Input.location.lastData.longitude + "," + Input.location.lastData.latitude;
            Debug.Log("定位信息" +  GetLocationByLngLat(str)); 
        }

        // Stop service if there is no need to query location updates continuously
        Input.location.Stop();
    }

地址解析 Geocoder

地址解析类用于在地址和经纬度之间进行转换的服务。 本功能以异步方式将检索条件发送至服务器，通过您自定义的回调函数将结果返回,也就是说我们可以通过经纬度换算出我们的位置详情，
代码如下；

  const string key = "6bda73179a87a92394489045b32a0f46";		//去高德地图开发者申请

    /// <summary>
    /// 根据经纬度获取地址
    /// </summary>
    /// <param name="LngLatStr">经度纬度组成的字符串 例如:"113.692100,34.752853"</param>
    /// <param name="timeout">超时时间默认10秒</param>
    /// <returns>失败返回"" </returns>
    public string GetLocationByLngLat(string LngLatStr, int timeout = 10000)
    {
        string url = $"http://restapi.amap.com/v3/geocode/regeo?key={key}&location={LngLatStr}";
        return GetLocationByURL(url, timeout);
    }

    /// <summary>
    /// 根据经纬度获取地址
    /// </summary>
    /// <param name="lng">经度 例如:113.692100</param>
    /// <param name="lat">维度 例如:34.752853</param>
    /// <param name="timeout">超时时间默认10秒</param>
    /// <returns>失败返回"" </returns>
    public string GetLocationByLngLat(double lng, double lat, int timeout = 10000)
    {
        string url = $"http://restapi.amap.com/v3/geocode/regeo?key={key}&location={lng},{lat}";
        return GetLocationByURL(url, timeout);
    }
    /// <summary>
    /// 根据URL获取地址
    /// </summary>
    /// <param name="url">Get方法的URL</param>
    /// <param name="timeout">超时时间默认10秒</param>
    /// <returns></returns>
    private string GetLocationByURL(string url, int timeout = 10000)
    {
        string strResult = "";
        try
        {
            HttpWebRequest req = WebRequest.Create(url) as HttpWebRequest;
            req.ContentType = "multipart/form-data";
            req.Accept = "*/*";
            //req.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)";
            req.UserAgent = "";
            req.Timeout = timeout;
            req.Method = "GET";
            req.KeepAlive = true;
            HttpWebResponse response = req.GetResponse() as HttpWebResponse;
            using (StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
            {
                strResult = sr.ReadToEnd();
            }
            int formatted_addressIndex = strResult.IndexOf("formatted_address");
            int addressComponentIndex = strResult.IndexOf("addressComponent");
            int cutIndex = addressComponentIndex - formatted_addressIndex - 23;
            int subIndex = formatted_addressIndex + 20;
            return strResult;
        }
        catch (Exception)
        {
            strResult = "";
        }
        return strResult;
    }

结果如下；

{"status":"1","regeocode":{"addressComponent":{"city":"福州市","province":"福建省","adcode":"350121","district":"闽侯县","towncode":"350121107000","streetNumber":{"number":"6号","location":"119.213622,26.0423319","direction":"东南","distance":"114.359","street":"高新大道"},"country":"中国","township":"上街镇","businessAreas":[[]],"building":{"name":[],"type":[]},"neighborhood":{"name":[],"type":[]},"citycode":"0591"},"formatted_address":"福建省福州市闽侯县上街镇高新大道"},"info":"OK","infocode":"10000"}