当相同的页面重新恳请的时候,且IsDefault差其余记录

筛选数据

急需:假设数据库中存在OrderNum相同,且IsDefault不一样的记录,那么IsDefault值为0的记录将替换值为1的笔录(IsDefault值为1的笔录不显示)。

图片 1

出于查出来的多寡不多,100条以内,所以作者是一直全体查询到List内存中,然后在内存中举办多少过滤的操作,思来想去都以为自家如下的贯彻形式很low,但是作者时期又没悟出好的章程,不明了我们有没有好的措施?

            var newList = list.ToList();
            //筛选出哪些排序号有重复
            var orderNumList = newList.GroupBy(g => g.OrderNum).Select(g => new { orderNum = g.Key, count = g.Count() }).Where(g => g.count > 1).Select(s => s.orderNum).ToList();
            var cfList = newList.Where(w => orderNumList.Contains(w.OrderNum)); //获取有重复排序号的记录

            var cfDefaultList = cfList.Where(w => w.IsDefault);  //默认模块记录
            var cfNoDefaultList = cfList.Where(w => w.IsDefault == false); //非默认模块记录

            var intersectedList = from d in cfDefaultList join f in cfNoDefaultList on d.OrderNum equals f.OrderNum where d.IsDefault!= f.IsDefault select d;

            var newIntersectedList = intersectedList.Distinct().ToArray(); //排序号相同,既存在默认记录也存在非默认记录的数据 

                if (newIntersectedList != null && newIntersectedList.Length > 0)
                {
                    for (int i = 0; i < newIntersectedList.Length; i++)
                    {
                        if (newList.Contains(newIntersectedList[i]))
                        {
                            newList.Remove(newIntersectedList[i]);
                        }
                    }
                }
           newList = newList.OrderBy(x => x.OrderNum).ToList();

 以上的newList就代码截图中的数据。

出口缓存Output caching

优化API接口

有一个API接口平时卡顿,而且很不平稳,快的时候2~3秒,慢的时候10秒去了。

接口需要:依据社区ID获取打折券记录。

分析:

  • 担负给API接口提供数据的连串中,缺少许多索引,存在很多慢查询视图。
  • 原本的LINQ完成格局是在内存中分页,响应速度太慢。
  • 并发请求的气象下,资源占用。

优化思路:

  数据缓存Data caching

1、使用缓存

同一个社区的人在同一时间所看到的促销券记录应当是均等的,而且大家相应允许脏读,大家在12306上面买高铁票的时候,常常也会看出突显有票,可是下单又没有了,大概是运用了缓存,那么大家那边实在同样的可以运用缓存来解决并发难题。

在WebAPI上边加缓存,那么又分为客户端缓存和服务器缓存。而小编辈领会,在ASP.NET
WebForm和ASP.NET
MVC中都是有页面输出缓存的,而在WebAPI中默许没有,从NuGet上边下载WebApi.OutputCache.V2,然后再API接口上添加 

[CacheOutput(ClientTimeSpan = 5)]//, ServerTimeSpan = 5

本身那里没办法直接使用服务器输出缓存,那是因为不可以捕获缓存变量参数。因为大家API接口的呼吁参数是string
appParam,字符串类型的,它是一个json对象进过base64位编码,然后再进过url编码生成的字符串。

笔者们只可以解析后,获取社区ID,然后根据社区ID来安装缓存,把社区ID+
pageIndex就当做缓存的Key,考虑到必要缓存的数据量很小,那里自个儿直接使用.NET自带的缓存,引入命名空间:System.Web.Caching;

      private static System.Web.Caching.Cache ObjCache = HttpRuntime.Cache;
        /// <summary>
        /// 设置当前指定Key的Cache值,并限定过期时间 
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        /// <param name="TimeOuts">超时时间(秒)</param>
        public static void SetCacheSeconds(string Key, object Obj, double TimeOuts)
        {
            ObjCache.Insert(Key, Obj, null, System.DateTime.Now.AddSeconds(TimeOuts), TimeSpan.Zero);
        }
        /// <summary>
        /// 获取当前指定Key的Cache值
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <returns>缓存的值</returns>
        public static object GetCache(string Key)
        {
            return ObjCache[Key];
        }

缓存操作类Cache完整代码如下:

图片 2图片 3

/*==================================
 * Author:
 * CreateTime:2014-7-15 17:26:29
 * Description:Cache操作类
 ===================================*/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Caching;
using System.Runtime.CompilerServices;
using System.Web;
using System.Security.Policy;

namespace SSY.Util
{
    /// <summary>
    /// 缓存处理相关类
    /// </summary>
    public class Cache
    {
        private static System.Web.Caching.Cache ObjCache = HttpRuntime.Cache;
        private static short TimeOut = 720;

        #region 清除指定键值的缓存
        /// <summary>
        /// 清除指定键值的缓存
        /// </summary>
        /// <param name="Key">要清除的缓存的key值</param>
        public static void Clear(string Key)
        {
            if (ObjCache[Key] != null)
            {
                ObjCache.Remove(Key);
            }
        }
        #endregion

        #region 返回系统中缓存的个数
        /// <summary>
        /// 返回系统中缓存的个数
        /// </summary>
        /// <returns>缓存个数</returns>
        public static int Count()
        {
            return ObjCache.Count;
        }
        #endregion

        #region 获取当前指定Key的Cache值
        /// <summary>
        /// 获取当前指定Key的Cache值
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <returns>缓存的值</returns>
        public static object GetCache(string Key)
        {
            return ObjCache[Key];
        }
        #endregion

        #region 设置当前指定Key的Cache值
        /// <summary>
        /// 设置当前指定Key的Cache值 
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        public static void SetCache(string Key, object Obj)
        {
            ObjCache.Insert(Key, Obj);
        }
        #endregion

        #region 设置当前指定Key的Cache值,并限定过期时间
        /// <summary>
        /// 设置当前指定Key的Cache值,并限定过期时间 
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        /// <param name="TimeOuts">超时时间(分钟)</param>
        public static void SetCache(string Key, object Obj, int TimeOuts)
        {
            ObjCache.Insert(Key, Obj, null, System.DateTime.Now.AddMinutes((double)TimeOuts), TimeSpan.Zero);
        }
        /// <summary>
        /// 设置当前指定Key的Cache值,并限定过期时间 
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        /// <param name="TimeOuts">超时时间(秒)</param>
        public static void SetCacheSeconds(string Key, object Obj, double TimeOuts)
        {
            ObjCache.Insert(Key, Obj, null, System.DateTime.Now.AddSeconds(TimeOuts), TimeSpan.Zero);
        }
        #endregion

        #region 设置当前指定Key的Cache值,依赖文件过期
        /// <summary>
        /// 设置当前指定Key的Cache值,依赖文件过期 
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        /// <param name="Files">相对地址,例如"~/files.xml"</param>
        public static void SetCache(string Key, object Obj, string Files)
        {
            CacheDependency cacheDep = new CacheDependency(System.Web.HttpContext.Current.Server.MapPath(Files),System.DateTime.Now);
            SetCache(Key, Obj, TimeOut, cacheDep, CacheItemPriority.High);
        }
        #endregion

        #region 设置当前指定Key的Cache值
        /// <summary>
        /// 设置当前指定Key的Cache值
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        /// <param name="Priority">撤销缓存的优先值,此参数的值取自枚举变量“CacheItemPriority”,优先级低的数据项将先被删除。此参数主要用在缓存退出对象时.</param>
        public static void SetCache(string Key, object Obj, CacheItemPriority Priority)
        {
            SetCache(Key, Obj, TimeOut, null, Priority);
        }
        #endregion

        #region 设置当前指定Key的Cache值
        /// <summary>
        /// 设置当前指定Key的Cache值
        /// </summary>
        /// <param name="Key">缓存Key</param>
        /// <param name="Obj">缓存的值</param>
        /// <param name="TimeOuts">一个TimeSpan,表示缓存参数将在多长时间以后被删除</param>
        /// <param name="CacheDep">缓存的依赖项,需要一个CacheDependency,可初始化一个</param>
        /// <param name="Priority">撤销缓存的优先值,此参数的值取自枚举变量“CacheItemPriority”,优先级低的数据项将先被删除。此参数主要用在缓存退出对象时</param>
        public static void SetCache(string Key, object Obj, int TimeOuts, CacheDependency CacheDep, CacheItemPriority Priority)
        {
            ObjCache.Insert(Key, Obj, CacheDep, System.DateTime.MaxValue, TimeSpan.FromHours((double)TimeOuts), Priority, null);
        }
        #endregion
    }
}

View Code

修改API接口代码:

           #region added by zouqj 2017-3-7
           var result = Util.Cache.GetCache(CommunityID+ pageIndex) as Result<List<GetAvailableCouponsModel>>;
           if (result==null) //不存在则写入缓存
           {
               //组装参数
               Dictionary<string, string> inParams = new Dictionary<string, string>();
               inParams.Add("UserId", userId);
               inParams.Add("PageIndex", pageIndex);
               inParams.Add("PageSize", pageSize);
               inParams.Add("CommunityID", CommunityID+ pageIndex);
               ...

               RequestParam RequestParam = GetRequestParam(methodName, inParams, AuthenticationId);
               var jsonContent = JsonConvert.SerializeObject(RequestParam);
               result = DoPost<List<GetAvailableCouponsModel>>(jsonContent, PostUrl);

               Util.Cache.SetCacheSeconds(CommunityID, result, 10); //写入缓存
           }
           return result;

  1. 出口缓存(Output Caching)

2、改为存储进程完毕

因为那几个接口的业务逻辑相比较复杂,此前的Linq代码写了好长一大串,获取的记录数很多,而且仍旧在内存中举行分页落成,所以本人将原本的LINQ已毕代码修改为分页存储进度达成。

积存进度代码如下:

图片 4图片 5

------------------------------------------创建领券中心存储过程 created by zouqj-2017-3-1-----------------------------------
IF EXISTS(Select Name From Sysobjects Where Name='usp_GetAvailableCoupons' And Xtype='P')
DROP PROCEDURE usp_GetAvailableCoupons
GO
CREATE PROC usp_GetAvailableCouponsl
(
@PageIndex int, --页码
@PageSize int, --每页容纳的记录数
@Sort NVARCHAR(50), --排序字段及规则,不用加order by
@hostName nvarchar(100),--服务器地址
@CommunityID UNIQUEIDENTIFIER, --社区
@IsGetCount BIT --是否得到记录总数,1为得到记录总数,0为不得到记录总数,返回记录集
)
AS
-------------------------------定义变量-----------------------
declare @strSql NVARCHAR(max);
DECLARE  @dt datetime2(7) --查询时间
SET @dt=GETDATE();
set nocount on;
----------------------------------------SQL开始--------------------------------------------无分类
IF @IsGetCount=1
BEGIN

SET @strSql=N'SELECT COUNT(*) FROM (SELECT DISTINCT t.CampaignID from
(SELECT 
c.ID AS CampaignID
 FROM MK_Campaign c WITH ( NOLOCK ) INNER JOIN MK_CouponConfig f WITH ( NOLOCK ) ON c.ID=f.CampaignID
           INNER JOIN MK_Coupon p WITH ( NOLOCK ) ON f.CouponID=p.ID
           WHERE f.CouponGetType=2 AND f.ReceiveStartTime <=@dt AND f.ReceiveEndTime>= @dt
           AND c.State=4 --执行中
           AND p.WholeNetwork=1 --全网优惠
UNION ALL
SELECT
    a.[ID] AS CampaignID
    FROM  [dbo].[MK_Campaign] AS a WITH ( NOLOCK )
        INNER JOIN [dbo].[MK_CouponConfig] AS b  WITH ( NOLOCK ) ON a.[ID] = b.[CampaignID]
        AND (b.[ReceiveStartTime] <= @dt) AND (b.[ReceiveEndTime] >= @dt) AND (2 = b.[CouponGetType]) AND (4 = a.[State]) 
        INNER JOIN [dbo].[MK_Coupon] AS c WITH ( NOLOCK ) ON b.[CouponID] = c.[ID]
        INNER JOIN [dbo].[MK_CouponRestriction] AS d  WITH ( NOLOCK ) ON c.[ID] = d.[CompainID]
        LEFT OUTER JOIN [dbo].[MK_CouponRestrictCategory] AS e WITH ( NOLOCK ) ON d.[ID] = e.[CouponRestrictionID]
        LEFT OUTER JOIN [dbo].[MK_CouponRestrictionOrg] AS f WITH ( NOLOCK ) ON d.[ID] = f.[CouponRestrictionID]
        INNER JOIN [dbo].[ViewOrganizationCommunityForInterface] AS v ON f.[OrgID] = v.[ID]    
    where v.CommunityID=@CommunityID  and 1 = d.[Type]
UNION ALL
SELECT 
   a.ID AS CampaignID
   FROM MK_Campaign a  WITH ( NOLOCK ) 
             INNER JOIN MK_CouponConfig b WITH ( NOLOCK ) ON a.ID=b.CampaignID AND (b.[ReceiveStartTime] <= @dt) AND (b.[ReceiveEndTime] >=@dt) 
             INNER JOIN [dbo].[MK_Coupon] AS c WITH ( NOLOCK ) ON b.[CouponID] = c.[ID] and (2 = b.[CouponGetType]) AND (4 = a.[State]) 
             INNER JOIN [dbo].[MK_CouponRestriction] AS d WITH ( NOLOCK ) ON c.[ID] = d.[CompainID]  AND (2 = d.[Type]) 
             LEFT OUTER JOIN MK_CouponRestrictionProduct AS e WITH ( NOLOCK ) ON d.[ID] = e.[CouponRestrictionID] 
             LEFT OUTER JOIN SL_Product AS f WITH ( NOLOCK ) ON (e.ProductID = f.ID)
             INNER JOIN ViewOrganizationCommunityForInterface v ON v.ID=f.PublisherID
   where v.CommunityID=@CommunityID
   ) t
 ) AS tt'
----------------------------------------------------------------------------------
END
ELSE
BEGIN
SET @strSql=N'SELECT DISTINCT t.* from(
SELECT 
          c.ID AS CampaignID,
          c.Name AS CampaignName,
          f.ValidityStartTime AS CampaignStartTime,
          f.ValidityEndTime AS CampaignEndTime,
          p.Name AS CouponsName,
          p.Price AS CouponsAmount,
          (CASE WHEN p.IsLimited =1 THEN 1 ELSE 2 END) AS IsLimited,
          p.FullAmount AS MinAmount,
          f.ValidityEndTime AS CouponsEndTime,
          f.ValidityStartTime AS CouponsStartTime,
          (CASE WHEN f.IsRepeateGet =1 THEN 1 ELSE 2 END) AS IsCanRepeatedReceive,
          f.ReceiveAddress AS ReceiveAddress,
          f.ReceiveEndTime AS ReceiveEndTime,
          f.ReceiveStartTime AS ReceiveStartTime,
          f.ReceiveMode AS ReceiveMethod,
          f.ProvideNum AS ReceiveNum,
          p.CreateTime AS CreateTime,
          p.Price AS Price,
          f.RemainCouponNum AS RemainCouponNum,
          f.ID AS CouponConfigId,
          p.WholeNetwork AS CouponsType,
          (CASE WHEN f.IconUrl IS NULL THEN N'''' WHEN f.IconUrl=N'''' THEN N'''' ELSE @hostName+f.IconUrl END) AS IconUrl 
FROM MK_Campaign c WITH ( NOLOCK ) 
                 INNER JOIN MK_CouponConfig f WITH ( NOLOCK ) ON c.ID=f.CampaignID
                 INNER JOIN MK_Coupon p WITH ( NOLOCK ) ON f.CouponID=p.ID
          WHERE f.CouponGetType=2 AND f.ReceiveStartTime <= @dt AND f.ReceiveEndTime>= @dt AND c.State=4 AND p.WholeNetwork=1 --全网优惠
--
UNION ALL
          SELECT a.[ID] AS CampaignID,
          a.[Name] AS CampaignName, 
          b.[ValidityStartTime] AS CampaignStartTime,
          b.[ValidityEndTime] AS CampaignEndTime, 
          c.[Name] AS CouponsName, 
          c.[Price] AS CouponsAmount, 
          CASE WHEN (c.[IsLimited] = 1) THEN 1 ELSE 2 END AS IsLimited, 
          c.[FullAmount] AS MinAmount, 
          b.[ValidityEndTime] AS CouponsEndTime, 
          b.[ValidityStartTime] AS CouponsStartTime, 
          CASE WHEN (b.[IsRepeateGet] = 1) THEN 1 ELSE 2 END AS IsCanRepeatedReceive, 
          b.[ReceiveAddress] AS [ReceiveAddress], 
          b.[ReceiveEndTime] AS [ReceiveEndTime], 
          b.[ReceiveStartTime] AS [ReceiveStartTime], 
          b.[ReceiveMode] AS ReceiveMethod, 
          b.[ProvideNum] AS ReceiveNum, 
          c.[CreateTime] AS CreateTime, 
          c.[Price] AS Price, 
          b.[RemainCouponNum] AS RemainCouponNum, 
          b.[ID] AS CouponConfigId, 
          e.[Type] AS CouponsType, 
          CASE WHEN (b.[IconUrl] = N'''' OR b.[IconUrl] IS NULL) THEN N'''' ELSE @hostName+b.[IconUrl] END AS IconUrl
                    FROM  [dbo].[MK_Campaign] AS a WITH ( NOLOCK )
                        INNER JOIN [dbo].[MK_CouponConfig] AS b  WITH ( NOLOCK ) ON a.[ID] = b.[CampaignID] AND (b.[ReceiveStartTime] <= @dt) AND (b.[ReceiveEndTime] >= @dt) AND (2 = b.[CouponGetType]) AND (4 = a.[State]) 
                        INNER JOIN [dbo].[MK_Coupon] AS c WITH ( NOLOCK ) ON b.[CouponID] = c.[ID]
                        INNER JOIN [dbo].[MK_CouponRestriction] AS d  WITH ( NOLOCK ) ON c.[ID] = d.[CompainID]
                        LEFT OUTER JOIN [dbo].[MK_CouponRestrictCategory] AS e WITH ( NOLOCK ) ON d.[ID] = e.[CouponRestrictionID]
                        LEFT OUTER JOIN [dbo].[MK_CouponRestrictionOrg] AS f WITH ( NOLOCK ) ON d.[ID] = f.[CouponRestrictionID]
                        INNER JOIN [dbo].[ViewOrganizationCommunityForInterface] AS v ON f.[OrgID] = v.[ID]    
                    where v.CommunityID=@CommunityID  and 1 = d.[Type]
UNION ALL
SELECT 
       a.ID AS CampaignID,
       a.Name AS CampaignName,
       b.ValidityStartTime AS CampaignStartTime,
       b.ValidityEndTime AS CampaignEndTime,
       c.Name AS CouponsName,
       c.Price AS CouponsAmount,
       (CASE WHEN c.IsLimited=1 then 1 else 2 END) AS IsLimited,
       c.FullAmount AS MinAmount,
       b.ValidityEndTime AS CouponsEndTime,
       b.ValidityStartTime AS CouponsStartTime,
       (case when b.IsRepeateGet=1 then 1 else 2 END) AS IsCanRepeatedReceive,
       b.ReceiveAddress AS ReceiveAddress,
       b.ReceiveEndTime AS ReceiveEndTime,
       b.ReceiveStartTime AS ReceiveStartTime,
       b.ReceiveMode AS ReceiveMethod,
       b.ProvideNum AS ReceiveNum,
       c.CreateTime AS CreateTime,
       c.Price AS Price,
       b.RemainCouponNum AS RemainCouponNum,
       b.ID AS CouponConfigId,
       d.[TYPE] AS CouponsType,
       (CASE WHEN b.IconUrl IS NULL THEN N'''' WHEN b.IconUrl=N'''' THEN N'''' ELSE @hostName+b.IconUrl END) AS IconUrl
   FROM MK_Campaign a  WITH ( NOLOCK ) 
                    INNER JOIN MK_CouponConfig b WITH ( NOLOCK ) ON a.ID=b.CampaignID AND (b.[ReceiveStartTime] <= @dt) AND (b.[ReceiveEndTime] >= @dt) 
                    INNER JOIN [dbo].[MK_Coupon] AS c WITH ( NOLOCK ) ON b.[CouponID] = c.[ID] and (2 = b.[CouponGetType]) AND (4 = a.[State]) 
                    INNER JOIN [dbo].[MK_CouponRestriction] AS d WITH ( NOLOCK ) ON c.[ID] = d.[CompainID]  AND (2 = d.[Type]) 
                    LEFT OUTER JOIN MK_CouponRestrictionProduct AS e WITH ( NOLOCK ) ON d.[ID] = e.[CouponRestrictionID] 
                    LEFT OUTER JOIN SL_Product AS f WITH ( NOLOCK ) ON (e.ProductID = f.ID)
                    INNER JOIN ViewOrganizationCommunityForInterface v ON v.ID=f.PublisherID
                    where v.CommunityID=@CommunityID
   ) t
ORDER BY t.Price--@Sort
offset (@PageIndex-1)*@PageSize ROWS  FETCH NEXT @PageIndex*@PageSize ROWS ONLY'
end
--执行SQL
exec sp_executesql @strSql,N'@PageIndex int,@PageSize int,@Sort nvarchar(50),@hostName nvarchar(100),@CommunityID UNIQUEIDENTIFIER,@IsGetCount bit,@dt datetime2(7)',@PageIndex =@PageIndex,@PageSize =@PageSize,@Sort=@Sort,@hostName=@hostName,@CommunityID=@CommunityID,@IsGetCount=@IsGetCount,@dt=@dt
set nocount off;

View Code

那边必要留意的是,存储执行是,先关闭计数,set nocount on;,然后再打开set
nocount off;,这样可以荣升品质。还有就是应用WITH ( NOLOCK
)允许脏读,升高查询效用。

此地境遇一个很奇怪的题材,小编使用exec
sp_executesql
@strSql,N’….’的法门来施行是未曾难点的,而若是本身使用拼接sql的措施,会报错,因为sql字符串被截断了,只截取到了4000个字符长度,即使作者把字符串变量长度设置为nvarchar(max)也没用。

分页方式使用Sqlserver2012以上版本才支撑的疾速格局:offset … FETCH NEXT
…ROWS ONLY

原先Linq的实践时间测试:

图片 6BLW.png)图片 7

自家修改为存储进度之后的履行时间测试:

图片 8

质量差别相当无不侧目。

  使用输出缓存,你可以缓存最后输出的HTML页面,当相同的页面重新恳请的时候,ASP.NET不会再实施页面的生命周期和连锁代码而是直接运用缓存的页面,语法如下:

  <%@
OutputCache Duration=”60” VaryByParam=”None”  %>

  Duration
属性设置页面将被缓存60妙。任何的用户请求都会被缓存,在缓冲的60秒内一样的央求都会直接行使缓存的页面。当缓存过期后ASP.NET会另行实施页面代码并且为下一个60秒创造一个新的HTML缓存。

<%@ Page Language=”C#” MastERPageFile=”~/MasterPage.master” AutoEventWireup=”true” CodeFile=”OutputCachingTest.aspx.cs” Inherits=”OutputCachingTest” Title=”Page” %> 
<%@ OutputCache Duration=”20″ VaryByParam=”None” %> 
<asp:Content ID=”Content1″ ContentPlaceHolderID=”ContentPlaceHolder1″ runat=”Server”>  
   <div class=”title”>Output
Cache</div> 
   Date: <asp:Label ID=”lblDate” runat=”server” Text=”” /> 
   Time: <asp:Label ID=”lblTime” runat=”server” Text=”” />        
</asp:Content>

 

protected void Page_Load(object sender, EventArgs e) 

  lblDate.Text = DateTime.Now.ToShortDateString(); 
  lblTime.Text = DateTime.Now.ToLongTimeString(); 
}

   在这么些事例中页面将被缓存20秒。

  透过查询字符串缓存(Cache by Query String )

  在骨子里运用中页面往往会依据一些参数动态的变动页面的始末。假诺你的页面是通过查询字符串来获取新闻的,你可以依据查询字符串很简单的缓存页面的不等拷贝。VarByParam=”None”指定ASP.NET只存储缓存页面的一个正片。VarByParam=”*”
指定ASP.NET按照区其余询问字符串存储不一样的缓存页面。

<%@ OutputCache
Duration=”60″ VaryByParam=”*” %> 
<div align=”right”> 
   <a href=”OutputCachingTest2.aspx”>No
Query String</a> |  
   <a href=”OutputCachingTest2.aspx?id=1″>ID
1</a> |  
   <a href=”OutputCachingTest2.aspx?id=2″>ID
2</a> |  
   <a href=”OutputCachingTest2.aspx?id=3″>ID
3</a> | 
   <a href=”OutputCachingTest2.aspx?id=3&langid=1″>ID
3</a> 
</div>

 

  上边的例证中,在询问字符串中传了差别的ID.ASP.NET为各个ID都存储了单独的缓存页面。那种形式会有部分难点就是当查问字符串范围很广的时候。

  这么些时候我们能够在VarByParam
属性中指定紧要的询问字符串变量的名字,如下:

  %@OutputCacheDuration=”60″VaryByParam=”id;langid”%

 

  那样,ASP.NET可以依据id” or “langid”来缓存分裂的缓存版本。

  自定义缓存(Custom Caching)

  你也得以创立自定义的先后来缓存页面。ASP.net提供了一种很便利的法子来创制自定义缓存,使用VarByCustom属性指定自定义缓存类型的名字。

  你还要创制为缓存生成自定义字符串的法门,如下:

  public override stringGetVaryByCustomString(HttpContext
context, stringcustom) 
  { 
  if(custom == “browser”) 
  { 
  returncontext.Request.Browser.Browser + 
  context.Request.Browser.MajorVersion; 
  } 
  else 
  { 
  return base.GetVaryByCustomString(context, custom); 
  } 
  }

 

  那个办法必须写在global.asax文件中。ASP.NET使用该方式重回的字符串来兑现缓存,尽管那几个主意在差其余哀告中回到相同的字符串,ASP.NET就会动用缓存的页面,否则就会转变新的缓存版本。

  下面的例子中GetVaryByCustomString()方法依照浏览器的名字创办缓存字符串,ASP.NET会按照差其他浏览器请求创制差距版本的缓存。

  控件缓存(Control Cache )

  上边的缓存技术可以让你很不难的缓存整个页面,即便要缓存指定控件的始末,可以通过点名VaryByControl
属性来完毕。

  %@OutputCacheDuration=”20″VaryByControl=”MyControl_1″%

 

  下面代码ASP.NET将会缓存MyControl_1控件20分钟。假如要基于一些属性值来缓存控件只要求将OutPutCache指令参加*.ascx页面。

<%@Control Language=”C#”AutoEventWireup=”true”CodeFile=”MyControl.ascx.cs” 
Inherits=”Controls_MyControl”%> 
<%@OutputCacheDuration=”20″VaryByControl=”EmployeeID”%>  

  VaryByControl=”EmployeeID”告诉ASP.NET依据控件中扬言的EmployeeID属性来创立分化版本的缓存。

  在 .ascx.cs 文件参与EmplyeeID属性为ASP.NET 缓存使用。

  在页面中追加控件并且安装 EmployeeID.

    private int_employeeID; 
  public intEmployeeID 
  { 
  get{ return_employeeID; } 
  set{ _employeeID = value;

  } 
  protected voidPage_Load(objectsender, EventArgs e) 
  { 
  lblDate.Text = DateTime.Now.ToShortDateString(); 
  lblTime.Text = DateTime.Now.ToLongTimeString(); 
  lblEmployeeID.Text = EmployeeID.ToString(); 
  }

 

     缓存配置文件(Cache Profile )

  Web.config可以配备缓存相关的安装,

  <system.web> 
  <caching> 
    <outputCacheSettings> 
      <outputCacheProfiles> 
        <addname=”ProductItemCacheProfile” duration=”60″/> 
      </outputCacheProfiles> 
    </outputCacheSettings> 
  </caching> 
</system.web>

 

   你可以经过设置 CacheProfile=”ProfileName” 属性 来利用方面的配备:

  %@OutputCacheCacheProfile=”ProductItemCacheProfile”VaryByParam=”None”%

 

  2. 数量缓存(Data Caching)

  ASP.net还提供了另一种灵活的缓存类型:数据缓存。你可以将部分消耗时间的条款出席到一个目的缓存集合中,以键值的章程存储。

  Cache[“Name”] = data;

  大家得以经过应用Cache.Insert()方法来安装缓存的晚点,优先级,看重项等。

  date1 = DateTime.Now;Cache.Insert(“Date1”, date1, null,
DateTime.Now.AddSeconds(20), TimeSpan.Zero);

  ASP.NET允许你设置一个纯属过期时间或滑动过期日子,但不能同时选拔。

  缓存看重项Cache dependency

  缓存倚重项使缓存正视于其余资源,当敬重项改成时,缓存条目项将机关从缓存中移除。缓存倚重项可以是应用程序的
Cache 中的文件、目录或与任何对象的键。要是文件或目录更改,缓存就会晚点。

    date2 = DateTime.Now; 
  string[] cacheKeys = { “Date1”}; 
  CacheDependency cacheDepn = newCacheDependency(null,
cacheKeys); 
  Cache.Insert(“Date2”, date2,
cacheDepn);

 

  上面的例证“Date2”缓存对象器重“Date1”缓存条目,当 “Date1”
对象过期后“Date2” 将会活动过期。CacheDependency(null,
cacheKeys)中的第二个参数为空是由于大家只监视缓存键的变更境况。

  回调函数和缓存优先级(Callback Method and Cache Priority)

  ASP.NET允许我们写一个回调函数,当缓存条目从缓存中移除的时候接触。仍能安装缓存条目的先期级。

  protected void Page_Load(object sender, EventArgs e) 
  { 
  DateTime? date1 = (DateTime?)Cache[“Date1”]; 
  if (!date1.HasValue) // date1 ==
null 
  { 
  date1 = DateTime.Now; 
  Cache.Insert(“Date1”,
date1, null, DateTime.Now.AddSeconds(20),
TimeSpan.Zero, 
  CacheItemPriority.Default, new CacheItemRemovedCallback(CachedItemRemoveCallBack)); 
  } 
  DateTime? date2 = (DateTime?)Cache[“Date2”]; 
  if (!date2.HasValue) // date2 ==
null 
  { 
  date2 = DateTime.Now; 
  Cache.Insert(“Date2”,
date2, null, DateTime.Now.AddSeconds(40),
TimeSpan.Zero, 
  CacheItemPriority.Default, new CacheItemRemovedCallback(CachedItemRemoveCallBack)); 
  } 
  // Set values in labels 
  lblDate.Text = date1.Value.ToShortDateString(); 
  lblTime.Text = date1.Value.ToLongTimeString(); 
  lblDate1.Text = date2.Value.ToShortDateString(); 
  lblTime1.Text = date2.Value.ToLongTimeString(); 
  } 
  private void CachedItemRemoveCallBack(string key, object value, CacheItemRemovedReason reason) 
  { 
  if (key == “Date1” || key == “Date2”) 
  { 
  Cache.Remove(“Date1”); 
  Cache.Remove(“Date2”); 
  } 
  }

 

  例子中开创了“Date1” 和 “Date2”缓存。“Date1”
在20秒后过期“Date2”为40秒。可是由于大家报了名了移除的回调函数,当“Date1”
或 “Date2”其中一个超时都会执行CachedItemRemoveCallBack
方法,在这么些点子中移除了七个缓存条目,ASP.NET还提供了拍卖缓存条目更新时的回调函数CacheItemUpdateCallback

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