怎么获取别人网站的数据？

怎么获取别人网站的数据？

给你一段代码。可以参照！
///

/// 获取开奖号码
///

///
public string GetNum(string Issue)
{
string number = "";
string url = "请填写你要抓取的地址";
string rl = null;
try
{
System.Net.WebRequest webRequest = System.Net.WebRequest.Create(url);
System.Net.WebResponse Response = webRequest.GetResponse();
Stream resStream = Response.GetResponseStream();
StreamReader sr = new StreamReader(resStream, Encoding.GetEncoding("GB2312"));
StringBuilder sb = new StringBuilder();
while ((rl = sr.ReadLine()) != null)
{
sb.Append(rl);
}
sr.Close();
resStream.Close();

string str = sb.ToString();
Regex rgLink = new Regex(@"<\s*link[^>]*([^<]|<(?!link))*/>", RegexOptions.IgnoreCase);
MatchCollection mcLink = rgLink.Matches(str);
foreach (Match matchLink in mcLink)
{
str = str.Replace(matchLink.Value, "");
}

Regex rgNum = new Regex(@"<\s*li[^>]*>([^<]|<(?!/li))*<\s*/li\s*>", RegexOptions.IgnoreCase);
MatchCollection mc = rgNum.Matches(str);
List list = new List();

Regex rgFind = new Regex(@"[0-9]{2}", RegexOptions.IgnoreCase);
foreach (Match match in mc)
{
string temp = match.Value;
Match m = rgFind.Match(temp);
list.Add(m.Value.Trim());
}
foreach (string v in list)
{
number += v;
}
return number;
}
catch (Exception)
{
return "False";
}

}

问题不清楚，举个例子出来或许明白点

为什么