一个天气预报服务接口

<%@ WebService Language="c#" Class="WeatherWS.GetChinaWeather" %>
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Net;
using System.Text;
using System.IO;
using System.Web;
using System.Web.Services;

namespace WeatherWS
{
 /// <summary>
 /// GetChinaWeather 的摘要说明。
 /// </summary>
 [WebService(Namespace="http://flying.redv.com/monster")]
 public class GetChinaWeather : System.Web.Services.WebService
 {
  public GetChinaWeather()
  {
   //CODEGEN: 该调用是 ASP.NET Web 服务设计器所必需的
   InitializeComponent();
  }

  #region 组件设计器生成的代码
  
  //Web 服务设计器所必需的
  private IContainer components = null;
    
  /// <summary>
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {
  }

  /// <summary>
  /// 清理所有正在使用的资源。
  /// </summary>
  protected override void Dispose( bool disposing )
  {
   if(disposing && components != null)
   {
    components.Dispose();
   }
   base.Dispose(disposing);  
  }
  
  #endregion

  [WebMethod(Description="中国各城市(县)天气预报获取服务,可接受一字符串参数（可选的查询方式：·国内城市（县）全名·字首拼音缩写·电话区号·邮政编码,如查询徐州的天气情况可输入'徐州'或'xz'作为参数）")]
  public DataSet getWeather(string strCity)
  {
   DataSet dsWeather = new DataSet();
   try
   {
    const int maxDay=5;
    string []time = new string[maxDay];//存储日期，从今天开始算起
    string []weather = new string[maxDay];//保存天气情况数据
    string []max = new string[maxDay];//保存最高温度数据
    string []min = new string[maxDay];//保存最低温度数据
    string []wind = new string[maxDay];//保存风向数据

    //发送一个post请求到index.jsp页面以获取城市数据
    Uri uri = new Uri("http://www.weathercn.com/forecastn/forcast/index.jsp?searchname="+System.Web.HttpUtility.UrlEncode(strCity,System.Text.Encoding.GetEncoding("GB2312")));
    WebRequest wreq=WebRequest.Create(uri);
  
    HttpWebResponse wresp=(HttpWebResponse)wreq.GetResponse();
  
    string HTML ="";

    Stream s=wresp.GetResponseStream();
  
    StreamReader objReader = new StreamReader(s,System.Text.Encoding.Default);
    HTML=objReader.ReadToEnd();
    if(HTML==null||HTML=="")
     return dsWeather;

    HTML = HTML.ToLower();//全部转换为小写
    if(HTML==null||HTML=="")
     return dsWeather;
    int head,tail,i;
    //查找城市数据 如果没有找到 则返回一个空的dataset
    head = HTML.IndexOf("查询结果：",0);
    head = HTML.IndexOf("station_name=",head);
    if(head==-1)
    {
     return dsWeather;
    }
    head = HTML.IndexOf("station_name=",head+1);
    tail = HTML.IndexOf("'",head);
    string strCityData = HTML.Substring(head,tail-head);//城市数据获取
    string href = "http://www.weathercn.com/forecastn/forcast/forecastDetail.jsp?"+strCityData;
    //根据城市数据去查询天气情况
    
    wreq=WebRequest.Create(href);
    wresp=(HttpWebResponse)wreq.GetResponse();
  
    HTML ="";
    s=wresp.GetResponseStream();
  
    objReader = new StreamReader(s,System.Text.Encoding.Default);
    HTML=objReader.ReadToEnd();
    if(HTML==null||HTML=="")
     return dsWeather;
    HTML = HTML.ToLower();//全部转换为小写
    
    DateTime dtNow = new DateTime();
    dtNow = DateTime.Today;//获取系统当前日期
    dtNow = dtNow.Subtract(TimeSpan.Parse("1"));
    for(i=0;i<maxDay;i++)
    {
     dtNow = dtNow.Add(TimeSpan.Parse("1"));
     time[i] = dtNow.ToShortDateString();//日期数据
    }
    
    //获取天气情况数据,总共maxDay天的数据
    String date = DateTime.Now.Year.ToString()+"年"+DateTime.Now.Month.ToString()+"月";//当前年月
    head = HTML.IndexOf(date,0);
    head = HTML.IndexOf("<tr>",head);
    for(i=0;i<maxDay;i++)
    {
     head = HTML.IndexOf("<td",head);
     head = HTML.IndexOf("<img",head);
     head = HTML.IndexOf("/",head);
     head = HTML.IndexOf("/",head+1);
     tail = HTML.IndexOf("_",head);
     weather[i] = HTML.Substring(head+1,tail-head-1);
     head = HTML.IndexOf("</td>",head);
    }

    //获取近maxDay天温度数据,包括最高温度和最低温度
    for(i=0;i<maxDay;i++)
    {
     head = HTML.IndexOf("max",head);
     head = HTML.IndexOf(">",head);
     tail = HTML.IndexOf("<",head);
     max[i] = HTML.Substring(head+1,tail-head-1);//最高温度

     head = HTML.IndexOf("min",head);
     head = HTML.IndexOf(">",head);
     tail = HTML.IndexOf("<",head);
     min[i] = HTML.Substring(head+1,tail-head-1);//最低温度
    }

    //最近maxDay天的风向数据
    head = HTML.IndexOf("<tr",head);
    for(i=0;i<maxDay;i++)
    {
     head = HTML.IndexOf("class",head);
     head = HTML.IndexOf(">",head);
     tail = HTML.IndexOf("<",head);
     wind[i] = HTML.Substring(head+1,tail-head-1);//风向数据
    }

    //将数据填充到DataSet中去
    DataTable dtWeather = new DataTable();
    dtWeather.Columns.Add("日期");
    dtWeather.Columns.Add("天气");
    dtWeather.Columns.Add("最高温度");
    dtWeather.Columns.Add("最低温度");
    dtWeather.Columns.Add("风力风向");
    for(i=0;i<maxDay;i++)
    {
     DataRow drWeather = dtWeather.NewRow();
     drWeather["日期"] = time[i];
     drWeather["天气"] = weather[i];
     drWeather["最高温度"] = max[i];
     drWeather["最低温度"] = min[i];
     drWeather["风力风向"] = wind[i];
     dtWeather.Rows.Add(drWeather);
    }
    dsWeather.Tables.Add(dtWeather);
    dsWeather.AcceptChanges();

    return dsWeather;

   }
   catch(Exception e)
   {
    //DO Something
    return dsWeather;
   }
  }
 }
}