我是个初学者，
问问大虾登陆的时候如何到数据库中验证。
给个例子。谢谢了

<!--#include virtual="/setup.asp" -->
<!--#include virtual="/inc/md5.asp" -->
<%top
select case Request("menu")
case ""
username=Request("username")
password=Request("password")
passcode=request("passcode")
if username="" then error("<li>登陆失败！用户名错误！")
if password="" then error("<li>登陆失败！密码错误！")
if passcode="" then error("<li>登陆失败！验证码错误！")
if not isnumeric(request.form("passcode")) then error("<li>登陆失败！验证码必须是数字，请正确填写！")
if Cint(request.form("passcode"))<>Session("GetCode") then error("<li>登陆失败！验证码错误！")
if not conn.Execute("Select username From [line] where username='"&username&"'" ).eof Then
lasttime=conn.execute("Select lasttime from [line] where username='"&username&"'")(0)
end if
if not conn.Execute("Select username From [line] where username='"&username&"'" ).eof Then error("<li>登陆失败，此用户已经登陆，请 <font color=red>"&((OnlineTime/60)+1)-(DateDiff("n",lasttime,Now()))&"</font> 分钟后在尝试！<br><li>您可以点击 <a href=/urse/chkuser.asp?menu=Clearance><font color=red>清除</font></a> ，清除相关信息后您可以在尝试登陆！")

set rs=server.CreateObject("adodb.recordset")
rs.Open "select * from [user] where username='"&username&"' and Password='"&md5(replace(trim(request.form("Password")),"'",""))&"' " ,conn,1,1
if rs.bof and rs.eof then error("<li>登陆失败！您的用户名或者密码错误！")
if rs("Activate")=1 then error("<li>登陆失败！您的帐户已被关闭，请联系我们！")
if rs("newmessage")<0 then
conn.execute("update [user] set newmessage=0 where username='"&username&"'")
end if
set rs=server.CreateObject("adodb.recordset")
rs.Open "select * from [user] where username='"&username&"' and Password='"&md5(replace(trim(request.form("Password")),"'",""))&"' " ,conn,1,3
if not(rs.bof and rs.eof) then
rs("lastvst")=now()
rs("loginnum")=rs("loginnum")+1
rs("IP")=Request.ServerVariables("REMOTE_ADDR")
Rs.update
rs.Close
Response.Cookies("oausername")=Request("username")
Response.Cookies("oapassword")=Request("password")
Response.Cookies("oaonlinetime")=now()
end if

case "out"
conn.execute("Delete From [line] Where username='"&Request.Cookies("oausername")&"'")
Response.Cookies("oausername")=""
Response.Cookies("oapassword")=""
Response.Cookies("oaonlinetime")=""

case "Clearance"
if not conn.Execute("Select ip From [line] where ip='"&Request.ServerVariables("REMOTE_ADDR")&"'" ).eof Then
conn.execute("Delete From [line] Where ip='"&Request.ServerVariables("REMOTE_ADDR")&"'")
end if

Response.Cookies("oausername")=""
Response.Cookies("oapassword")=""
Response.Cookies("oaonlinetime")=""
message="<li>清除清除相关信息成功！</a><li><a href=/urse/login.asp>返回后尝试登陆</a>"
succeed(""&message&"<meta http-equiv=refresh content=3;url=/urse/login.asp>")
end select

message="<li>操作成功!<li><a href=../index.asp>返回网站首页</a><li><a href=../bbs/index.asp>返回论坛首页</a>"
succeed(""&message&"<meta http-equiv=refresh content=3;url=../index.asp>")
%>


开始写的,蛮简单的,就是有些乱和语法错误~做初学者的例子应该没问题

uid=replace(request("uid"),"'","")
pwd=replace(request("pwd"),"'","")
sql="select id,uid,pass,coname,en,qb_1 from qb_co where uid='"&uid&"'"
rs.open sql,conn,1,1
if rs.eof or rs.bof then
response.write "<script>alert('没有"&uid&"这个用户！');history.go(-1);</Script>"
Response.End
end if
if rs(2)<>pwd then
response.write "<script>alert('密码错误！');history.go(-1);</Script>"
Response.End
end if

非常感谢斑竹。
爱死你了