logincheck.asp
<!--#include file="conn.asp"-->
<%
username=request.form("username")
if username<>"" then
set rs=server.createobject("adodb.recordset")
rs.open "select username from usertable",conn,1,1
if rs.eof Then
session("username")=username
response.write("<script language=javascript>alert('错误的用户名');window.history.go(-1);</script>")
response.end
End If
End If
%>
没有验证,楼主试一下