网页中添加新浪天气预报的几种方法_[Asp.Net教程]
1.利用新浪提供给的iframe直接嵌入，这种方式非常的简单，但是却没有交互性。代码如下：
2.抓取当天的天气，以指定格式输出。
涉及的核心代码如下：

public static ArrayList GetWeather(string code)
{
/*
[0] "北京 "string
[1] "雷阵雨 "string
[2] "9℃" string
[3] "29℃"string
[4] "小于3级"string
*/
string html = "";
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://weather.sina.com.cn/iframe/weather/" + code + "_w.html ");
request.Method = "Get";
//request.Timeout = 1;
request.ContentType = "application/x-www-form-urlencoded ";
WebResponse response = request.GetResponse();
Stream s = response.GetResponseStream();
StreamReader sr = new StreamReader(s, System.Text.Encoding.GetEncoding("GB2312"));
html = sr.ReadToEnd();
s.Close();
sr.Close();
}
catch (Exception err)
{
throw new Exception("访问地址出错~~~ ");
}

int count = html.Length;
int starIndex = html.IndexOf("
int endIndex = html.IndexOf("
", starIndex, count - starIndex);
html = html.Substring(starIndex, endIndex - starIndex + 8);

//得到城市
int cityStartIndex = html.IndexOf("", 0, html.Length);
int cityEndIndex = html.IndexOf("", 0, html.Length);
string City = html.Substring(cityStartIndex + 3, cityEndIndex - cityStartIndex - 3);


//得到天气
int weatherStartIndex = html.IndexOf("", cityEndIndex);
int weatherEndIndex = html.IndexOf("", weatherStartIndex);
string Weather = html.Substring(weatherStartIndex + 3, weatherEndIndex - weatherStartIndex - 3);

//得到温度

int temperatureStartIndex = html.IndexOf(" int temperatureEndIndex = html.IndexOf("", weatherEndIndex + 3);
string Temperature = html.Substring(temperatureStartIndex + 21, temperatureEndIndex - temperatureStartIndex - 21);

int int1 = Temperature.IndexOf("℃", 0);
int int2 = Temperature.IndexOf("～", 0);
int int3 = Temperature.IndexOf("℃", int2);

string MinTemperature = Temperature.Substring(int2 + 1, int3 - int2);
string MaxTemperature = Temperature.Substring(0, int2 - int1 + 2);

//得到风力
int windforceStartIndex = html.IndexOf("风力：", temperatureEndIndex);
int windforceEndIndex = html.IndexOf("
", windforceStartIndex);
string Windforce = html.Substring(windforceStartIndex + 3, windforceEndIndex - windforceStartIndex - 3);

if (Windforce.Contains("小于") && (!Windforce.Contains("等于"))) //判断风力是否含有"小于"或"小于等于"字样将,如果有的话，将其替换为2-
{
//Windforce = Windforce.Replace("小于", "2-");
string strWindforce = Windforce.Substring(2, Windforce.Length - 3);
int minWindforce = Int32.Parse(strWindforce) - 1;
Windforce = Windforce.Replace("小于", minWindforce.ToString() + "-");

}
else if (Windforce.Contains("小于等于"))
{
string strWindforce = Windforce.Substring(4, Windforce.Length - 5);
int minWindforce = Int32.Parse(strWindforce) - 1;
Windforce = Windforce.Replace("小于等于", minWindforce.ToString() + "-");
}

ArrayList al = new ArrayList();
al.Add(City);
al.Add(Weather);
al.Add(MinTemperature);
al.Add(MaxTemperature);
al.Add(Windforce);

return al;
}
这里涉及到一个ConvertCode类，它的作用是用于把城市转换为对应的全国统一的编码，