ASP实例 使用缓存提高数据显示效率
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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> （编辑：银川站长网） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |
