//获得页面文件
    private string RetrieveContent(string webPage)
    {

        if (webPage.Equals(" about:blank ")) return null;
        if (!webPage.StartsWith(" http:// ") && !webPage.StartsWith(" https:// "))
        {
            webPage = " http:// " + webPage;
        }
        //Response.Write("<script>alert('" + webPage + "');</script>");

        //到这里弹出是正常勒，　　　　　　

        HttpWebResponse response = null;
        StreamReader respStream = null;
        try
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(webPage);
            request.Timeout = 1000;  //设置超时时间（ms）
            request.Method = "GET";
            request.UserAgent = " User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;) ";
            request.Accept = " */* ";
            request.KeepAlive = true;
            request.Headers.Add(" Accept-Language ", " zh-cn,en-us;q=0.5 ");

            response = (HttpWebResponse)request.GetResponse();

            respStream = new StreamReader(response.GetResponseStream());

            return respStream.ReadToEnd();
        }
        catch (Exception ex)
        {

            throw ex;
        }
        finally
        {

            //关闭
          response.Close();
            respStream.Close();
        }
    }