难道是因为在这个地方，我放了个本人在我的小站的链接地址，就违反了首页的规则，这绝对的原创，我星星苦苦写的，虽说没有很高的技术含量，但也是有点的，在放一次，如果被撤下来，希望能给我个合理的解释。在此，谢谢园子里了的管理人员。
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。
文章在我小站的地址：Web Service学习笔记：利用YAHOO公开API做天气预报Web服务
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
>
其中最重要的是后面的几行，查询当天和第二天的天气情况，我们要获取的天气信息就在里面，代码如下：
<
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
"
/>
我们所需要用到的Node是/rss/channel/item/yweather: forecast；这个节点里的东西是我们需要的。
知道了这些，我们接下来要做的就是在VS中建立WEB服务，并添加下面的代码：
namespace
Weather
{
/**//// 
/// Weather 的摘要说明
/// [WebService(Name = "WeatherWebService", Namespace = "http://www.h2bbs.com/Weather/Weather.asmx", Description = "利用YAHOO公开的API接口，在Web服务实现公开的天气预报调用服务。")] [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] [ToolboxItem(false)] public class Weather : System.Web.Services.WebService { [WebMethod(Description = "根据城市的名称返回该城市的天气预报情况，只能查询省会和直辖市的天气情况。")] public DataSet GetWeather(string strCityName) { string strXml = "http://xml.weather.yahoo.com/forecastrss?p=CHXX" + CityNameToCityNum(strCityName); XmlDocument Weather = new XmlDocument(); Weather.Load(strXml); XmlNamespaceManager namespacemanager = new XmlNamespaceManager(Weather.NameTable); namespacemanager.AddNamespace("yweather", "http://xml.weather.yahoo.com/ns/rss/1.0"); XmlNodeList nodes = Weather.SelectNodes("/rss/channel/item/yweather:forecast", namespacemanager); //XmlNodeList nodes = Weather.GetElementsByTagName("forecast", "http://xml.weather.yahoo.com/ns/rss/1.0"); DataSet dstWeather = new DataSet(); DataTable dtblWeather = new DataTable("Weather"); dstWeather.Tables.Add(dtblWeather); dstWeather.Tables["Weather"].Columns.Add("Date", typeof(string)); dstWeather.Tables["Weather"].Columns.Add("Week", typeof(string)); dstWeather.Tables["Weather"].Columns.Add("Weather", typeof(string)); dstWeather.Tables["Weather"].Columns.Add("Tlow", typeof(string)); dstWeather.Tables["Weather"].Columns.Add("Thigh", typeof(string)); if (nodes.Count > 0) { foreach (XmlNode node in nodes) { DataRow drowWeather = dstWeather.Tables["Weather"].NewRow(); drowWeather["Date"] = EmonthToCmonth(node.SelectSingleNode("@date").Value.ToString()); drowWeather["Week"] = EweekToCweek(node.SelectSingleNode("@day").Value.ToString()) + "(" + node.SelectSingleNode("@day").Value.ToString() + ")"; drowWeather["Weather"] = node.SelectSingleNode("@text").Value; drowWeather["Tlow"] = FToC(int.Parse(node.SelectSingleNode("@low").Value)) + "℃"; drowWeather["Thigh"] = FToC(int.Parse(node.SelectSingleNode("@high").Value)) + "℃"; dstWeather.Tables["Weather"].Rows.Add(drowWeather); } return dstWeather; } else { DataRow drowNone = dstWeather.Tables["Weather"].NewRow(); drowNone["Date"] = "None"; drowNone["Week"] = "None"; drowNone["Weather"] = "None"; drowNone["Tlow"] = "None"; drowNone["Thigh"] = "None"; dstWeather.Tables["Weather"].Rows.Add(drowNone); return dstWeather; } } /**//// /// 从华氏转换成摄氏 /// /// /// private string FToC(int f) { return Math.Round((f - 32) / 1.8, 1).ToString(); } /**//// /// 从星期英文缩写转汉字 /// /// /// private string EweekToCweek(string strEweek) { switch (strEweek) { case "Mon": return "星期一"; break; case "Tue": return "星期二"; break; case "Wed": return "星期三"; break; case "Thu": return "星期四"; break; case "Fri": return "星期五"; break; case "Sat": return "星期六"; break; case "Sun": return "星期日"; break; default: return "传参错误"; break; } } /**//// /// 从月英文缩写转汉字 /// /// /// private string EmonthToCmonth(string strReplace) { return Convert.ToDateTime(strReplace).ToString("yyyy年MM月dd日"); } /**//// /// 根据城市名称返回城市编号 /// /// /// private string CityNameToCityNum(string strCityNameToNum) { //中国各个省会和直辖市对应的查询代码 Hashtable htWeather = new Hashtable(); htWeather.Add("北京", "0008"); htWeather.Add("天津", "0133"); htWeather.Add("杭州", "0044"); htWeather.Add("合肥", "0448"); htWeather.Add("上海", "0116"); htWeather.Add("福州", "0031"); htWeather.Add("重庆", "0017"); htWeather.Add("南昌", "0097"); htWeather.Add("香港", "0049"); htWeather.Add("济南", "0064"); htWeather.Add("澳门", "0512"); htWeather.Add("郑州", "0165"); htWeather.Add("呼和浩特", "0249"); htWeather.Add("乌鲁木齐", "0135"); htWeather.Add("长沙", "0013"); htWeather.Add("银川", "0259"); htWeather.Add("广州", "0037"); htWeather.Add("拉萨", "0080"); htWeather.Add("海口", "0502"); htWeather.Add("南宁", "0100"); htWeather.Add("成都", "0016"); htWeather.Add("石家庄", "0122"); htWeather.Add("贵阳", "0039"); htWeather.Add("太原", "0129"); htWeather.Add("昆明", "0076"); htWeather.Add("沈阳", "0119"); htWeather.Add("西安", "0141"); htWeather.Add("长春", "0010"); htWeather.Add("兰州", "0079"); htWeather.Add("西宁", "0236"); htWeather.Add("南京", "0099"); object cityNum = htWeather[strCityNameToNum]; if (cityNum == null) { return "City not found"; } else { return cityNum.ToString(); } } }
}
别忘了"using System.Xml;"哦！
Web服务的代码中有一个Web公开方法，四个私有方法：
（1）GetWeather方法是公共方法，提供Web调用。
（2）FToC方法，他主要是把RSS返回的华氏温度转换成摄氏温度，其实这一步可以不用的，当初没发现，URL中加点参数就返回的是摄氏温度。
（3）EweekToCweek方法，他主要是把英文的星期缩写变成中文。
（4）EmonthToCmonth方法，它主要是把英文的月份缩写变成中文，并重新排序。
（5）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，所以就只能支持这么几个城市了，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。
查询个中国随便的省会，效果如下
xml version
=
"
1.0
"
encoding
=
"
utf-8
"
?>
-
<
DataSet xmlns
=
"
http://www.h2bbs.com/WebService/Weather.asmx
"
>
-
<
xs:schema id
=
"
NewDataSet
"
xmlns
=
""
xmlns:xs
=
"
http://www.w3.org/2001/XMLSchema
"
xmlns:msdata
=
"
urn:schemas-microsoft-com:xml-msdata
"
>
-
<
xs:element name
=
"
NewDataSet
"
msdata:IsDataSet
=
"
true
"
msdata:UseCurrentLocale
=
"
true
"
>
-
<
xs:complexType
>
-
<
xs:choice minOccurs
=
"
0
"
maxOccurs
=
"
unbounded
"
>
-
<
xs:element name
=
"
Weather
"
>
-
<
xs:complexType
>
-
<
xs:sequence
>
<
xs:element name
=
"
Date
"
type
=
"
xs:string
"
minOccurs
=
"
0
"
/>
<
xs:element name
=
"
Week
"
type
=
"
xs:string
"
minOccurs
=
"
0
"
/>
<
xs:element name
=
"
Weather
"
type
=
"
xs:string
"
minOccurs
=
"
0
"
/>
<
xs:element name
=
"
Tlow
"
type
=
"
xs:string
"
minOccurs
=
"
0
"
/>
<
xs:element name
=
"
Thigh
"
type
=
"
xs:string
"
minOccurs
=
"
0
"
/>
xs:sequence
>
xs:complexType
>
xs:element
>
xs:choice
>
xs:complexType
>
xs:element
>
xs:schema
>
-
<
diffgr:diffgram xmlns:msdata
=
"
urn:schemas-microsoft-com:xml-msdata
"
xmlns:diffgr
=
"
urn:schemas-microsoft-com:xml-diffgram-v1
"
>
-
<
NewDataSet xmlns
=
""
>
-
<
Weather diffgr:id
=
"
Weather1
"
msdata:rowOrder
=
"
0
"
diffgr:hasChanges
=
"
inserted
"
>
<
Date
>
2008年10月14日
Date
>
<
Week
>
星期二(Tue)
Week
>
<
Weather
>
Clear
Weather
>
<
Tlow
>
16.1
℃
Tlow
>
<
Thigh
>
26.7
℃
Thigh
>
Weather
>
-
<
Weather diffgr:id
=
"
Weather2
"
msdata:rowOrder
=
"
1
"
diffgr:hasChanges
=
"
inserted
"
>
<
Date
>
2008年10月15日
Date
>
<
Week
>
星期三(Wed)
Week
>
<
Weather
>
Sunny
Weather
>
<
Tlow
>
16.7
℃
Tlow
>
<
Thigh
>
28.3
℃
Thigh
>
Weather
>
NewDataSet
>
diffgr:diffgram
>
DataSet
>
写完了！最后希望能给大家带来收获！