开发你的LBS应用，使用Google地图引擎，根据地理位置获取纬度、经度。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Text.RegularExpressions;
using System.IO;
using System.Web;
using Tiwer.Config;

namespace Tiwer.Data
{
public class TGoogleMap
{
private string address;
private string url;

private string latitude;
/// <summary>
/// 纬度
/// </summary>
public string Latitude
{
get { return latitude; }
}

private string longitude;
/// <summary>
/// 经度
/// </summary>
public string Longitude
{
get { return longitude; }
}

public DGoogleMap(string location)
{
SetAddress(location);
GetMapInfo();
}

/// <summary>
/// 获取经度
/// </summary>
/// <param name="location">地址</param>
/// <returns>经度</returns>
public string GetLongtitude(string location)
{
GetMapInfo();

return longitude;
}

/// <summary>
/// 获取纬度
/// </summary>
/// <param name="location">地址</param>
/// <returns>纬度</returns>
public string GetLatitude( string location)
{
SetAddress(location);
GetMapInfo();

return latitude;
}

/// <summary>
/// 获取地图经纬信息
/// </summary>
private void GetMapInfo()
{
HttpWebRequest searchRequest = (HttpWebRequest)WebRequest.Create(@url);
searchRequest.ServicePoint.Expect100Continue = false;

WebResponse myresponse = searchRequest.GetResponse();
Stream responseStream = myresponse.GetResponseStream();

byte[] buffer = new byte[99];
responseStream.Read(buffer, 0, (int)99);

myresponse.Close();

string results = System.Text.Encoding.ASCII.GetString(buffer);
string[] arr = results.Split(',');

latitude = arr[2].ToString();
longitude = arr[3].ToString().Substring(0, 10);
}

/// <summary>
/// 设置地址
/// </summary>
/// <param name="location">地址</param>
private void SetAddress(string location)
{
IConfigManager _iconfig = ConfigManagerFactory.CreateConfigManager("general");
string _key = _iconfig.GetElementValue("GoogleMapKey")["GoogleMapKey"];

address = HttpUtility.UrlEncode(location);
url = "http://203.208.39.99/maps/geo?q=" + address + "&output=csv&oe=utf8&sensor=true_or_false&key=" + _key;
}

/// <summary>
/// 获取经度
/// </summary>
/// <param name="location">地址</param>
/// <returns>经度</returns>
public static string DGetLongtitude(string location)
{
DGoogleMap map = new DGoogleMap(location);
return map.Longitude;
}

/// <summary>
/// 获取纬度
/// </summary>
/// <param name="location">地址</param>
/// <returns>纬度</returns>
public static string DGetLatitude(string location)
{
DGoogleMap map = new DGoogleMap(location);
return map.Latitude;
}
}
}