白色盲虾 可以耐热450:有谁能帮我解释一下下面的程序 一句句的解释 谢谢

<!-- #include file="top.asp" -->
<!-- #include file="chksession.asp" -->
<%
response.buffer=true

Aucid=rst("aucid")
'得到被评价者ID
Toid=rst("cid")
if not(isNum(aucid) and isNum(Toid)) then
Call ErrAlert("对不起，参数传递有错！请返回!","",0)
else
%>

<table width="772" border="0" cellspacing="0" cellpadding="0" align=center>
<tr>
<td width="150" align="left" valign="top">
<!--#include file="left.asp" -->
</td>
<td width="5"> </td>
<td align="left" valign="top">
<table width='100%' border=0 cellpadding=4 cellspacing=0 id='b1'>
<tr>
<td height='10' colspan='2'></td>
</tr>
<tr>
<td height='25' >您的位置：信用管理 〉成交做信用评价</td>
</tr>
</table>
<table width="100%" border="0" cellspacing="0" cellpadding="0" id="b1">
<tr>
<td width="4" valign="top" id="bg11"> </td>
<td width="100" align="center" valign="bottom" id="bg11"><font color="#ffffff">请选择评价对象</font></td>
<td width="4" valign="top" id="bg11"> </td>
<td> </td>
</tr>
<tr>
<td height="2" colspan="4" id="bg11"></td>
</tr>
</table>
<%
if rst("action")="save" then

if rst("r1")=2 then
leixing="好"
end if
if rst("r1")=1 then
leixing="中"
end if
if rst("r1")=0 then
leixing="差"
end if
'--------------------查询自己的 id-------------------------
myregid=session(super_user&"uid")

set rsrecord=server.createobject("adodb.recordset")
sql = "select * from pingjia where aucid="&rst("aucid")&" and pingjiazheid="& session(super_user&"uid")
rsrecord.open sql,conn,1,3
if not rsrecord.eof then
response.write "<script language=javascript>alert('你已经做过此次交易的信用评价！');this.location.href='home.asp';</script>"
response.end
end if