用C#读取sina天气预报到wap页面

ding.GetEncoding("GB2312").GetBytes(paraUrlCoded); //将URL编码后的字符串转化为字节 
request.ContentLength = payload.Length; //设置请求的ContentLength
Stream writer = request.GetRequestStream(); //获得请求流
writer.Write(payload,0,payload.Length); //将请求参数写入流
writer.Close(); //关闭请求流
HttpWebResponse response;
response = (HttpWebResponse)request.GetResponse(); //获得响应流
Stream s;
s = response.GetResponseStream();
StreamReader objReader = new StreamReader(s,System.Text.Encoding.GetEncoding("GB2312"));
string HTML = "";
string sLine = "";
int i = 0; 
while (sLine!=null) 
...{
i++;
sLine = objReader.ReadLine();
if (sLine!=null) 
HTML += sLine;
} 
HTML = HTML.Replace("<","<");
HTML = HTML.Replace(">",">");
int start,stop;
start = HTML.IndexOf("<img src="http://image2.sina.com.cn/dy/weather/images/figure/",0,HTML.Length);
stop = HTML.IndexOf("<td background=http://image2.sina.com.cn/dy/weather/images",start); 
temp = HTML.Substring(start, stop - start);
}
catch (Exception x)
...{
}
return temp;
}
}