asp.net vb版 cache 处理缓存实例

简单的实例，cache方法理解ASP.NET缓存 Cache之数据缓存

大家可以通过各种各样的方法去优化我们系统，本篇博文将介绍通过Cache方法来优化系统的性能，减轻系统的负担。

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="cache.aspx.vb" Inherits="admin_cache" %>






    


    

    

     
                            
    
    

Imports System.Web.Caching
Partial Class admin_cache
    Inherits System.Web.UI.Page

    Shared itemRemoved As Boolean = False
    Shared reason As CacheItemRemovedReason
    Dim onRemove As CacheItemRemovedCallback
    Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
       
        '缓存技术，首先判断是否有缓存数据
        If (itemRemoved) Then
            Response.Write("RemovedCallback event raised.")
            Response.Write("
")
            Response.Write("Reason: " + reason.ToString() + "")
        Else
            Response.Write("Value of cache key: " + Server.HtmlEncode(CType(Cache("Key1"), String)) + "")
        End If

    End Sub
    Public Sub RemovedCallback(k As String, v As Object, r As CacheItemRemovedReason)
        itemRemoved = True
        reason = r
    End Sub
    Public Sub AddItemToCache(sender As Object, e As EventArgs)
        '添加缓存数据，同时触发onRemove事件，itemRemoved变成真
        onRemove = New CacheItemRemovedCallback(AddressOf Me.RemovedCallback)

        If (IsNothing(Cache("Key1"))) Then
            Cache.Add("Key1", "这里是缓存数据", Nothing, DateTime.Now.AddSeconds(10), Cache.NoSlidingExpiration, CacheItemPriority.High, onRemove)
        End If
    End Sub

    Public Sub RemoveItemFromCache(sender As Object, e As EventArgs)
        '移除缓存数据
        If (Not IsNothing(Cache("Key1"))) Then
            Cache.Remove("Key1")
        End If
    End Sub
End Class