用C#实现FTP搜索引擎

晚辈最近用C#写了一个教育网FTP搜索引擎，希望能得到高手的指点。

网址：http://soso.ccnu.com.cn      http://it.ccnu.edu.cn/soso

部分代码：

using System;
using softplib;
using System.Threading;
using System.Collections;
using System.Net;
using System.Net.Sockets;
using System.IO;
using System.Data;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
namespace spider
{
 /// <summary>
 /// IndexClass 的摘要说明。
 /// </summary>
 //编制索引类
 class IndexClass
 {
  private IPAddress ip;
  private string name;
  private SqlProcedure sp;
  public IndexClass(IPAddress _ip,string _name)
  {
   ip=_ip;
   name=_name;
  
  }

  public void createIndex()
  {
   FTPFactory ff = new FTPFactory();
   ff.setDebug(false);
   string header="ftp://"+ip.ToString();
   string address=name;
   try
   {
    ff.setRemoteHost(ip.ToString());
    ff.login();
    Queue q=new Queue();
    ArrayList fileNames=ff.getFileList("*.*");
    ArrayList subdirNames=ff.getSubdir("*",ref fileNames);
    if(fileNames!=null && fileNames.Count>0)
     foreach(string s in fileNames)
     {
     
      try
      {
       Console.WriteLine(header+"/"+s);
       int h=-1;
       long _size=0;
       try
       {
        _size=ff.getFileSize(s);
        h=s.IndexOf("/");
       }
       catch
       {
        _size=0;
        Console.WriteLine("size error");
       }

       if(s!=null && s.Trim()!="")
       {
        DataUnit datau=new DataUnit(s,_size,header+"/",DateTime.Now,ip.ToString(),address);
        Class1.DataQueue.Enqueue(datau);
       }
      }
      catch(Exception ex){Console.WriteLine(ex.Message);};
     }
    if(subdirNames!=null && subdirNames.Count>0)
     foreach(string s in subdirNames)
     {
      if(s.Equals("..") || s.Equals("."))continue;
      if(s!=null && s.Trim()!="")
      {
       q.Enqueue("/"+s);
       DataUnit datau=new DataUnit(s,(long)0,header+"/",DateTime.Now.AddHours(1),ip.ToString(),address);
       Class1.DataQueue.Enqueue(datau);
      }
     }
    while(q.Count>0)
    {
     string parent=q.Dequeue() as string;
     //Console.WriteLine("change to "+parent.Trim());

     try
     {
      ff.chdir(parent.Trim());
     
     }
     catch
     {
      Console.WriteLine(parent.Trim());
      ff.setRemoteHost(ip.ToString());
      ff.login();
      Console.WriteLine("=======Continue========");
      continue;
     }
     fileNames=ff.getFileList("*.*");
     subdirNames=ff.getSubdir("*",ref fileNames);
     if(fileNames!=null && fileNames.Count>0)
      foreach(string s in fileNames)
      {
     
       try
       {
        Console.WriteLine(header+parent+"/"+s);
        long _size=0;