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string strconnection = "server=localhost;uid=sa;password=wxj;database=notebook;";
  SqlConnection thisconnection = new SqlConnection(strconnection);
  thisconnection.Open();
  SqlCommand thiscommand = new SqlCommand("select brand,grabfrom from brand", thisconnection);
  SqlDataReader thisread = thiscommand.ExecuteReader();

  WebClient mywebclient = new WebClient();
  mywebclient.Credentials = CredentialCache.DefaultCredentials;
  int number = 0;
  SqlCommand sqlcommand_successful = null;
  string brand = "";
  string grab_test= "";
  while (thisread.Read())
  {
  brand += thisread["brand"].ToString();
  grab_test += thisread["grabfrom"].ToString();
   
  number++;
  Console.WriteLine("这是中关村手机的第" + number + "品牌!" + " " +brand + "\n\n");
  byte[] mybyte = mywebclient.DownloadData(grab_test);
  string mystring = Encoding.Default.GetString(mybyte);


  Regex re = new Regex(@"条,(?<page>[\s\S]*?)\s页");
  MatchCollection mc = re.Matches(mystring);
  int testabc = 0;
  testabc++;
  int testint = 0;

  foreach (Match m in mc)
  {

  string test = m.Groups["page"].ToString();
  int i = int.Parse(test);

  for (int ztx = 1; ztx <= i; ztx++)
  {


  WebClient webclient2008 = new WebClient();
  webclient2008.Credentials = CredentialCache.DefaultCredentials;
  //thisread["grabfrom"].ToString().Replace("1", "3")
  byte[] byte2008 = webclient2008.DownloadData(grab_test.Replace("_1.html", "_" + ztx.ToString() + ".html"));
  string string2008 = Encoding.Default.GetString(byte2008);
  Regex re2 = new Regex(@"<div class=""pro_img"">[\s\S]*?href=""(?<grab1>[\s\S]*?)""[\s\S]*?src=""(?<small_image>[\s\S]*?)""");
  MatchCollection mc2 = re2.Matches(string2008);
  foreach (Match m2 in mc2)
  {


  // Console.WriteLine(testabc + m2.Groups["grab1"].ToString() + m2.Groups["small_image"].ToString());
  // string abc = m2.Groups["grab1"].ToString();
  // Console.WriteLine(abc);


  WebClient webclient_end = new WebClient();
  webclient_end.Credentials = CredentialCache.DefaultCredentials;
  byte[] end_byte = webclient_end.DownloadData(m2.Groups["grab1"].ToString());
  string end_string = Encoding.Default.GetString(end_byte);
  Regex regex_end = new Regex(@"id=""td_param"">[\s\S]*?href=""(?<grab2>[\s\S]*?)""");
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