疯了，if和else同时执行了，怎么办？
以下是我的代码，在调试中发现if和else同时执行了。请大侠解释一下：
<!--#include   virtual= "/Public/Conn.asp "-->
<%
dim   userName
dim   userTypeID,Pwd,SafeEmail,LinkMan,Sex,Phone
dim   sql,k
dim   s
userTypeID   =   Trim(Request.Form( "userTypeID "))
Pwd   =   Trim(Request.Form( "Pwd "))
SafeEmail   =   Trim(Request.Form( "SafeEmail "))
LinkMan   =   Trim(Request.Form( "LinkMan "))
Sex   =   Trim(Request.Form( "Sex "))
Phone   =   Trim(Request.Form( "Phone "))
userName   =   Trim(request.Form( "Name "))

sql= "select   [Name]   from   userinfo   where   [Name]   =   ' "   &   userName   &   " ' "
Set   k   =   Server.CreateObject( "Adodb.Recordset ")
k.open   sql,cn,1,3
If   k.eof   and   k.bof   Then
sql= "insert   into   UserInfo(userTypeID,Name,Pwd,SafeEmail,LinkMan,Sex,Phone)   values( "&userTypeID& ", ' "&userName& " ', ' "&Pwd& " ', ' "&SafeEmail& " ', ' "&LinkMan& " ', ' "&Sex& " ', ' "&Phone& " ') "
cn.Execute   sql
Set   s   =   cn.Execute( "select   *   from   userinfo   where   ID   =   (SELECT   MAX(ID)   FROM   UserInfo) ")
If   Not   (s.EOF   And   s.bof)   Then
session( "username ")   =   s( "Name ")
session( "userInfoID ")   =   s( "ID ")
session( "userTypeID ")   =   s( "userTypeID ")
End   If
else
Response.Write   " <script   language= 'javascript '> "
Response.Write   "       alert( '此用户名已存在! '); "
Response.Write   "       history.back(); "
Response.Write   "       </script> "
response.End()
end   if
k.close
set   k=nothing
cn.Close
%>
用户名在数据库明明是不存在的，他执行的时候，好像先插入了数据，然后又提示永明已经存在，真不知道是怎么回事？

------解决方案--------------------
If k.eof and k.bof Then 换别的试试呢

If k.eof or k.bof Then

If k.eof Then

If not k.eof Then ---- 反一反试试
------解决方案--------------------
能否调试一下看看几时候插入数据的阿.
------解决方案--------------------
还有是否程序执行了两遍啊?
------解决方案--------------------
sql= "insert into UserInfo(userTypeID,Name,Pwd,SafeEmail,LinkMan,Sex,Phone) values( "&userTypeID& ", ' "&userName& " ', ' "&Pwd& " ', ' "&SafeEmail& " ', ' "&LinkMan& " ', ' "&Sex& " ', ' "&Phone& " ') "
cn.Execute sql

换成 rs.addnew 方式 试试
------解决方案--------------------
你反过来写吧。
If not(k.eof or err) Then
err
else
addnew
end if

------解决方案--------------------
在else前加上response.end()