当前位置: 首页 > 图文教程 > 网络编程 > ASP > ASP实例:利用缓存提高数据显示效率

ASP
VPN技术详解(下)
微软Page Counter 组件参考(一)
微软Page Counter 组件参考(二)
@ 指令参考之一 - @CODEPAGE
@ 指令参考之二 - @ENABLESESSIONSTATE
@ 指令参考之三 - @LANGUAGE
@ 指令参考之四 - @LCID
@ 指令参考之五 - @TRANSACTION
SQL数据操作基础(初级) 1
SQL数据操作基础(初级) 2
SQL数据操作基础(初级) 3
Response对象1
Response对象2
Response对象3
Response对象4
Response对象5
WSH简介
WSH实用讲座:第一讲 获取机器的网络属性配置
WSH实用讲座---第二讲 创建用户、目录和站点
WSH实用讲座---第三讲 创建邮箱

ASP实例:利用缓存提高数据显示效率


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-08-14   浏览: 128 ::
收藏到网摘: n/a

实例演示:先建立一个简单的数据库,写个function读取一下,写入一个dim变量temp中:

ASP代码

以下为引用的内容:
<%       
Function DisplayRecords()       
    Dim sql, conn, rs       
    sql = "SELECT id, [szd_f], [szd_t] FROM admin"      
    Set conn = Server.CreateObject("ADODB.Connection")       
    conn.Open "DRIVER={Microsoft Access Driver (*.mdb)}; DBQ="&Server.MapPath("db.mdb")       
    Set rs = Server.CreateObject("ADODB.Recordset")       
    rs.Open sql, conn, 1, 3
    If Not rs.EOF Then      
      Dim temp       
      temp = "<table width=""90%"" align=""center"""      
      temp = temp & " border=""1""  bordercolor=""silver"""      
      temp = temp & " cellspacing=""2"" cellpadding=""0"">"      
      temp = temp & "<tr bgcolor=""#CCDDEE""><td width=""5%"""      
      temp = temp & ">ID</td><td>操作</td>"
      temp = temp & "<td>数值</td></tr>"
    While Not rs.EOF       
      temp = temp & "<tr><td bgcolor=""#CCDDEE"">"      
      temp = temp & rs("ID") & "</td><td>" & rs("szd_f")       
      temp = temp & "</td><td>" & rs("szd_t")       
      temp = temp & "</td></tr>"      
      rs.MoveNext       
    Wend
      temp = temp & "</table>"
      DisplayRecords = temp       
    Else      
      DisplayRecords = "Data Not Available."      
    End If
    rs.Close       
    conn.Close       
    Set rs = Nothing      
    Set conn = Nothing      
End Function
'写入缓存       
Function DisplayCachedRecords(Secs)       
    Dim retVal, datVal, temp1       
        retVal = Application("cache_demo")       
        datVal = Application("cache_demo_date")
        If datVal = "" Then      
            datVal = DateAdd("s",Secs,Now)       
        End If
        temp1 = DateDiff("s", Now, datVal)      
    If temp1 > 0 And retVal <> "" Then      
        DisplayCachedRecords = retVal
        ' Debugging Code :       
        Response.Write "<b><font color=""green"">利用缓存读取数据"      
        Response.Write " ... (" & temp1 & " 秒剩余)</font></b>"      
        Response.Write "<br><br>"      
    Else
        Dim temp2       
        ' Change DisplayRecords() to the function whose        
        ' value you want to cache       
        temp2 = DisplayRecords()
        Application.Lock       
            Application("cache_demo") = temp2       
            Application("cache_demo_date") = DateAdd("s",Secs,Now)       
        Application.UnLock
        DisplayCachedRecords = temp2
        ' Debugging Code :       
        Response.Write "<b><font color=""red"">刷新缓存显示 ..."      
        Response.Write "</font></b><br><br>"
    End If      
End Function      
%>       
<!--       
Response.Write DisplayRecords()       
-->
<html>       
<head>       
    <title>利用缓存从数据库---读取数据</title>       
    <style>       
    body, p, td { font-family:Sans-Serif; font-size:8pt; }       
    td { padding-left: 5; }       
    </style>       
</head>       
<body>       
<%       
    Dim t1, t2       
        t1 = Timer       
    Response.Write DisplayCachedRecords(20)       
        t2 = Timer       
%>
<p align="center">       
停留时间: <%= Left((CDbl((t2 - t1) * 1000.0)), 5) %> ms       
</p>
</body>       
</html>