调用高德地图接口

    一

 //1需要先请求接口

  WebClient client = new WebClient(); 

     //2把接口转换成byte数据   

        Byte[] byteTest = client.DownloadData("https://restapi.amap.com/v3/geocode/geo?address=" + 地址+                                       "&output=JSON&key=你申请的key");

//3转换成字符串
        string data = Encoding.UTF8.GetString(byteTest);   

 //4反序列化
        JObject obj = (JObject)JsonConvert.DeserializeObject(data); 

//4经纬度

string a1 = obj["geocodes"][0]["location"].ToString();

二

//计算两经纬度之间的距离

 Byte[] byteTest3 = client.DownloadData("https://restapi.amap.com/v3/direction/driving?origin= " + 经纬度1+ " &destination=" + 经纬度2+ "&output=JSON&key=你申请的key");

 string data3 = Encoding.UTF8.GetString(byteTest3);
  JObject obj3 = (JObject)JsonConvert.DeserializeObject(data3);
   int a = ConvertHelper.GetInteger(obj3["route"]["paths"][0]["distance"]);