Question

asp怎么判断数据库的用户名字段或密码字段是否为空？？

下面这段代码是用于登录的asp页面代码，由VB程序提交到这个登录页面的。我想在这个页面增加一段代码来修改成的效果是：首先查询数据库，如果user字段不为空,但dl字段为空，则提示:'未激活’。然后如果dl字段不为空才执行登录代码。

原先的登录代码如下：

<%@LANGUAGE="VBSCRIPT" CODEPAGE="936"%>
<%option explicit%>
<%response.Expires=0%>
<%
private sub main()
dim dl,pass,state,errmsg

dl=request("dl")
pass=request.form("pass")

state=0
errmsg=""
if len(dl)=0 then
state=1
errmsg="用户名不能为空"
response.Write(errmsg)
exit sub
end if
if instr(1,dl," ")<>0 then
state=1
errmsg="用户名里面不能有空格"
response.Write(errmsg)
exit sub
end if
if instr(1,dl,"'")<>0 then
state=1
errmsg="用户名里面含有非法字符"
response.Write(errmsg)
exit sub
end if
if len(pass)=0 then
state=1
errmsg="密码不能为空"
response.Write(errmsg)
exit sub
end if
%>
<!--#include file="conn.asp" -->
<%
rs.open "select * from Users where Dl='" & dl & "' and Pass='" & pass & "'",con,1,1

if rs.bof and rs.eof then
rs.close
con.close
set rs=nothing
set con=nothing

state=1
errmsg="登陆失败，用户名或密码错误！！！"
response.Write(errmsg)
exit sub
else

rs.close
con.close
set rs=nothing
set con=nothing

state=0

'session("user")=user
response.Write("ok")
exit sub
end if
end sub

call main()
%>

请高手帮下，给完整代码，，谢谢了
有人知道吗？或者给我段如何判断的代码，如果表格里的user字段不为空，但dl字段为空，then 这个表达式如何写呢？
1楼的答案加上去后好像没用啊

Answer 1

又修改了下：

<%
rs.open "select * from Users where user='" & dl & "' and Pass='" & pass & "'",con,1,1

if rs.bof and rs.eof then
rs.close
con.close
set rs=nothing
set con=nothing

state=1
errmsg="登陆失败，用户名或密码错误！！！"
response.Write(errmsg)
exit sub
else

if IsNull(rs("dl")) or rs("dl") = "" then
state=1
errmsg="该账号未激活！！！"
response.Write(errmsg)
exit sub
end if

rs.close
con.close
set rs=nothing
set con=nothing

state=0

'session("user")=user
response.Write("ok")
exit sub
end if
end sub

call main()
%>