实现ASP缓存技术

1.服务器端缓存

    ListBox=Application("ListBox")

    If ListBox<>"" then

        Response.Write "本次通过服务器缓存读取数据:<BR>"

    End If

    If ListBox="" then

        Response.Write "本次为第一次读取数据，从数据库中读取:<BR>"

        Response.Write "另外打开窗口读取或者刷新页面即可验证从服务器缓存中读取数据<BR>"

        Set Conn=Server.CreateObject("ADODB.Connection")

        Conn.ConnectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & Server.Map("Book.mdb")

        Conn.Open

        Set rs=Server.CreateObject("ADODB.Recordset")

        sql="select * from book"

        set rs=conn.Execute(sql)

        ListBox="<select>"

        '用一个循环把Recordset赋值给ListBox变量

        Do Until rs.Eof

             ListBox=ListBox & "<option>" & rs("book_press") & "</option>"

             rs.MoveNext

        Loop

        rs.Close

        Set rs=nothing

        ListBox=ListBox & "</select>"

        Application("ListBox")=ListBox

    End If    

    Reponse.Write Application("ListBox")

    用了简单的Application变量后，可以发现服务器上的请求数量会降低不少，这种方法尤其适合那些更新不是很频繁的网站

2.客户端缓存

    客户端缓存技术也叫断开连接的ADO技术，主要用来保护用户的个人信息，密码，代号等，如在Global.asa中，添加如下代码

<script language="vbscript" runat="Server">

    Sub Applicaion_OnStart()

        Set Conn=Server.CreateObject("ADODB.Connection")

        Conn.ConnectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & Server.MapPath("user.mdb")

        Conn.Open

        Set rs=Server.CreateObject("ADODB.RecordSet")

        sql="select username,password from userinfo"

        rs.CursorLocation=3

        rs.Open sql,Conn,3,1

        set rs.ActiveConnection=Nothing

        set Application("rs")=rs

    End Sub

</script>

在User.Asp中，添加如下代码

set youruser=Application("rs").Clone

set yourname=yourusers("username")

set password=yourusers("password")

Do Until yourusers.Eof

    Response.Write "您的姓名:" & username

    Response.Write "您的密码:" & password

    yourusers.MoveNext

loop