利用YAHOO公开API做天气预报Web服务

系列文章导航：

创建一个示例和WebMethod特性解析

WebService特性和数组类型解析

类和结构体解析

利用YAHOO公开API做天气预报Web服务

Webservice 的设计和模式

Remoting和Webservice的区别

学了一段时间的Web服务，今天做了一个Web服务，利用YAHOO的公开天气API做自己的Web服务，主要是想练练手。现在把过程和心得分享给大家。

求教：这个Web服务还有个不完善的地方，Web服务的CityNameToCityNum方法，这个最重要，他是把省会和直辖市的名字转换为编号，因为YAHOO传的参数不是城市名字的区号，全是自己的，而我又想不到更好的获得YAHOO城市对应的编号的方法，所以就创建了HASHTABLE存储了中国的各个省会城市和直辖市，希望有高手提出更好的方法，能不用这样，直接找YAHOO获取编号，提取更多的城市，而不用把所有的中国所有的城市全写在HASHTABLE里。

Web服务地址：http://www.h2bbs.com/Weather/Weather.asmx

 

原理：

 在Yahoo的Developer Network

http://developer.yahoo.com/weather/

详细地介绍了Yahoo天气预报的API调用方法，这里用C#来实现，本文主要是利用它的API做Web服务，其它的应用由网友们自由发挥

首先了解Yahoo Weather Api的RSS Response格式(这是下午我查我家银川天气时返回的RSS)：

 

xml version = " 1.0 "  encoding = " UTF-8 "  standalone = " yes "   ?>
< rss version = " 2.0 "  xmlns:yweather = " http://xml.weather.yahoo.com/ns/rss/1.0 "  xmlns:geo = " http://www.w3.org/2003/01/geo/wgs84_pos# " >
   < channel >
     < title > Yahoo !  Weather  -  Yinchuan, CH title >
     < link > http: // us.rd.yahoo.com/dailynews/rss/weather/Yinchuan__CH/*[url] http://weather.yahoo.com/forecast/CHXX0259_f.html [/url]
     < description > Yahoo !  Weather  for  Yinchuan, CH description >
     < language > en - us language >
     < lastBuildDate > Tue,  14  Oct  2008   11 : 00  am CST lastBuildDate >
     < ttl > 60 ttl >
     < yweather:location city = " Yinchuan "  region = ""   country = " CH " />
     < yweather:units temperature = " F "  distance = " mi "  pressure = " in "  speed = " mph " />
     < yweather:wind chill = " 56 "   direction = " 360 "   speed = " 4 "   />
     < yweather:atmosphere humidity = " 56 "   visibility = " 999 "   pressure = ""   rising = " 0 "   />
     < yweather:astronomy sunrise = " 7:03 am "   sunset = " 6:19 pm " />
     < image >
       < title > Yahoo !  Weather title >
       < width > 142 width >
       < height > 18 height >
       < link > http: // weather.yahoo.com
       < url > http: // l.yimg.com/us.yimg.com/i/us/nws/th/main_142b.gif
     image >
     < item >
       < title > Conditions  for  Yinchuan, CH at  11 : 00  am CST title >
       < geo:lat > 38.48 geo:lat >
       < geo: long > 106.22 geo: long >
       < link > http: // us.rd.yahoo.com/dailynews/rss/weather/Yinchuan__CH/*[url] http://weather.yahoo.com/forecast/CHXX0259_f.html [/url]
       < pubDate > Tue,  14  Oct  2008   11 : 00  am CST pubDate >
       < yweather:condition  text = " Mostly Cloudy "   code = " 28 "   temp = " 56 "   date =
" Tue, 14 Oct 2008 11:00 am CST "   />
       < description >
         [CDATA[
< img src = "
[img]http: // l.yimg.com/us.yimg.com/i/us/we/52/28.gif[/img]"/>
< b > Current Conditions: b >< br  />
Mostly Cloudy,  56  F < BR  />
< BR  />< b > Forecast: b >< BR  />
Tue  -  Mostly Cloudy. High:  68  Low:  47 < br  />
Wed  -  Partly Cloudy. High:  70  Low:  44 < br  />
< br  />
< a href = " Full'>http://us.rd.yahoo.com/dailynews/rss/weather/Yinchuan__CH/*http://weather.yahoo.com/forecast/CHXX0259_f.html " > Full Forecast at Yahoo !  Weather a >< BR />
(provided by The Weather Channel) < br />
]] >
       description >
       < yweather:forecast day = " Tue "  date = " 14 Oct 2008 "  low = " 47 "  high = " 68 "  text
= " Mostly Cloudy "  code = " 28 "   />
       < yweather:forecast day = " Wed "  date = " 15 Oct 2008 "  low = " 44 "  high = " 70 "  text
= " Partly Cloudy "  code = " 30 "   />
       < guid isPermaLink = " false " > CHXX0259_2008_10_14_11_00_CST guid >
     item >
   channel >
rss >