解释ASP代码

<%

DeleteMember = Session("Member")

BeginPos = Instr(Application("Member"),DeleteMember)

EndPos = BeginPos+Len(DeletMember)+4 '4=Len("<BR>")

if BeginPos >0 then

Application.Lock

LeftMember =Left(Application("Member")),BeginPos-1)

RightMember =Left(Application("Member"),EndPos)

Application("Member") = LeftMember & RightMember

application("Num") = Application("Num")-1

application.unlock

%>

每行解释一下谢谢各位

DeleteMember = Session("Member") '//获取存贮的用户信息Member

BeginPos = Instr(Application("Member"),DeleteMember) '//获得用户信息在Application("Member")中的开始位置

EndPos = BeginPos+Len(DeletMember)+4 '//获得用户信息在Application("Member")中的结束位置

if BeginPos >0 then '开始位置在于0,即本用户信息在Application("Member")中

Application.Lock '//锁定Application

LeftMember =Left(Application("Member")),BeginPos-1)

RightMember =Left(Application("Member"),EndPos)

Application("Member") = LeftMember & RightMember

'//以上内容是去掉Session("Member")中用户的信息

application("Num") = Application("Num")-1 '//

application.unlock '//解锁

'==========================

'这段程序不就是统计|记录在线用户吗

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