php 读取 google 地图经纬度

参考了网上部分资料，自己改写了一个方便的获取经纬度信息的类geo，其中latitude和longtitude分别是纬度和经度。其中最重要的构造函数就是传入地名，通过webrequest从google map获得经纬度值，在含有地理位置信息的项目里可以很方便的调用，即geo g = new geo("北京师范大学");然后g.latitude和g.longtitude就是北京师范大学的纬度和经度了，它们分别是39.9614580，116.3692820。geo的实现如下：

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;

namespace YourNameSpace
{
    ///

    /// a class for latitude and longtitude
    ///

    [Serializable]
    public class Geo
    {
        ///

        /// latitude
        ///

        private string _latitude = "";

        ///

        /// longtitude
        ///

        private string _longtitude = "";

        ///

        /// default constructor
        ///

        public Geo()
        {

        }

        ///

        /// construct geo given latitude and longtitude
        ///

        ///
        ///
        public Geo(string latitude, string longtitude)
        {
            _latitude = latitude;
            _longtitude = longtitude;
        }
       
        ///

        /// construct geo given name of a place
        ///

        ///
        public Geo(string location)
        {
            string output = "csv";
            string url = string.Format("http://maps.google.com/maps/geo?q={0}&output={1}", location, output);
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            using (StreamReader sr = new StreamReader(response.GetResponseStream()))
            {
                string[] tmpArray = sr.ReadToEnd().Split(',');
                _latitude = tmpArray[2];
                _longtitude = tmpArray[3];
            }
        }

        ///

        /// get latitude(纬度)
        ///

        public string Latitude
        {
            get { return _latitude; }
            set { _latitude = value; }
        }

        ///

        /// get longtitude(经度)
        ///

        public string Longtitude
        {
            get { return _longtitude; }
            set { _longtitude = value; }
        }
    }