C#获取网页源代码的方法

public string GetPageHTML(string url){ try {  HttpWebRequest wr = WebRequest.Create(url) as HttpWebRequest;  wr.Method = "get";  wr.Accept = "*/*";  wr.Headers.Add("Accept-Language: zh-cn");  wr.Headers.Add("UA-CPU: x86");  wr.Headers.Add("Accept-Encoding: gzip, deflate");  wr.UserAgent = "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Embedded Web Browser from: http://bsalsa.com/; InfoPath.2; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022)";  wr.KeepAlive = true;  wr.ServicePoint.Expect100Continue = false;  wr.AllowAutoRedirect = false;  HttpWebResponse wre = wr.GetResponse() as HttpWebResponse;  StreamReader sreader = new StreamReader(wre.GetResponseStream(), Encoding.GetEncoding("GBK"));  string sHtml = sreader.ReadToEnd();  wre.Close();  return sHtml; } catch {  return ""; }}