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
ASP基础讲座(下)
解决IIS5 HTTP500内部错误
ASP 3.0高级编程(四十六)
ASP 3.0高级编程(四十五)
ASP 3.0高级编程(四十四)
ASP 3.0高级编程(四十三)
ASP 3.0高级编程(四十二)
ASP 3.0高级编程(四十一)
ASP 3.0高级编程(三十九)
ASP 3.0高级编程(三十八)
ASP 3.0高级编程(三十七)
ASP 3.0高级编程(三十六)
ASP 3.0高级编程(三十五)
ASP 3.0高级编程(三十四)
ASP 3.0高级编程(三十三)
ASP 3.0高级编程(三十二)
ASP 3.0高级编程(三十一)
ASP错误代码说明
jscript错误代码及相应解释大全
ASP错误处理

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: 66 ::
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>