ASP uses three layer mode to realize simple AJAX message Board

For a long time did not write ASP, this time to write a message board really feel a little difficult, the competition has written a whole day, haha.
There is nothing else to write, the use of three-layer structure (do not know, the original three-layer concept is very confused)

Demo www.zj55.com Message board, I hope you Big Brother elder sister if found that there is a loophole please tell me here, do not black my website, here Brother first thanked.

Index.asp
<%@ codepage=65001%>
<%
Option Explicit
%>
<% response.charset= "Utf-8" %>
<% session.codepage=65001%>
<!--#include file= "acchelper.asp"
<!--#include file= "Common.asp" The
<!--#include file= "dal_guest.asp";
<!--#include file= "mod_guest.asp"-->
<!--#include file= "bll_guest.asp"
<%
Dim mybll
Dim MyList
Set Mybll = new Bll_guest
Select case Request ("Tcmd")
Case "SAVE"
Mybll. Insert ()
Case "DEL"
Mybll. Delete ()
End Select
myList = mybll. Findbypage ()
%>
<p>
<form name= "Subform" id= "Subform"
<textarea id= "con" name= "con" cols= "rows=" "6" wrap= "VIRTUAL" ></TEXTAREA>
<input type= "button" Name= "Submit" value= "submitted Message" onclick= "$ (' guest/index.asp?tcmd=save&content= ' +escape (this.form.con.value))"
</form>
</p>
<%=mylist%>

Bll_guest.asp
<%
'///<summary>
'///Summary description.
'///</summary>
Class Bll_guest

Private Mycom,mymod,mydal

Private Li,ul

Private DEL

' Get information
Public Sub getguest ()

Mydal. Getguest (ID)

End Sub

' New information
Public Sub Insert ()

Mymod. Content = Request ("content")
Mymod.re = Request ("Re")
Mymod. Addtime = Now ()
Mymod. Ip = Request.ServerVariables ("Http_x_forwarded_for")
If Len (mymod. Ip) <=0 Then mymod. Ip = Request.ServerVariables ("REMOTE_ADDR")

Call Mydal. Insert (Mymod)

End Sub

' Update information
Public Sub Update ()

Call Mydal. Update (Mymod)

End Sub

' Delete Information
Public Sub Delete ()

Mydal. Delete (Request ("Id")

End Sub

' Find information
Public Function Findbypage ()

Dim Pagesize,currentpage,wherevalue,ordervalue,recordcount
Dim objRS
Dim Tmp1,tmp2,tmp3,parms,i
Dim Tcmd
Tcmd = Request ("Tcmd")
PageSize = "8"
CurrentPage = Request ("PageNo")
If Len (currentpage) <=0 Then
Currentpage=1
End If
Wherevalue = ""
OrderValue = "Id"
Set objRS = Mydal. Findbypage (Pagesize,currentpage-1,wherevalue,ordervalue)
i = 1
RecordCount = Mydal. Count (Wherevalue)
Do as Not objrs.eof
If tcmd= "DEL" Then
DEL = "<a tcmd=del&id=" &objrs ("Id") & "" > Delete </a>
Else
DEL = ""
End If
Parms=array (I,objrs ("content"), objRS ("IP"), objRS ("Addtime"), DEL)
TMP1 = TMP1 & mycom. Format (li,parms)
Objrs.movenext
i = i + 1
Loop
Tmp3 = mycom. Page (Pagesize,currentpage,recordcount, "guest/index.asp?tcmd=list")
Parms=array (Tmp1,tmp3)
TMP2 = TMP2 & mycom. Format (ul,parms)

Findbypage = TMP2

End Function

Private Sub Class_Initialize ()

LI = "<li><span>{0}</span> <span>{1}</span><br/><span> Author: {2}</span > <span>{3}</span> <span>{4}</span></li> "& vbCrLf
UL = "<UL>{0}<li>{1}</li></UL>"
DEL = ""

Set mycom = new Common
Set mymod = new Mod_guest
Set mydal = new Dal_guest

End Sub

Private Sub Class_Terminate ()

Set mycom = Nothing
Set Mymod = Nothing
Set mydal = Nothing

End Sub

End Class
%>

Dal_guest.asp
<%
'///<summary>
'///Summary description.
'///</summary>
Class Dal_guest

Private sql_01
Private sql_02
Private sql_03
Private sql_04
Private sql_05
Private sql_06
Private sql_07

Private Mycom,myacc,mymod

'///<summary>
'///Get information
'///</summary>
'///<param name= ' Id > Judgment field </param>
'///<returns> information body </returns>
Public Function getguest (Id)

Dim Parms,sql,objrs
Parms = Array (Id)
SQL = mycom. Format (sql_01,parms)
Set objRS = Myacc. ExecuteReader (MYACC. Conn_string,sql)
If Not objRS.EOF Then
Call Mymod. SetVar (objRS ("Id"), objRS ("Content"), objRS ("Re"), objRS ("Addtime"), objRS ("Ip")
Set getguest = Mymod
Else
Getguest = Null