当相同的页面重新恳请的时候,不明了大家有没有好的方法

筛选数据

急需:假诺数据库中留存OrderNum相同,且IsDefault差别的记录,那么IsDefault值为0的笔录将替换值为1的笔录(IsDefault值为1的记录不呈现)。

图片 1

是因为查出来的多寡不多,100条以内,所以本身是直接全部查询到List内部存储器中,然后在内存中开始展览多少过滤的操作,思来想去都觉得本人如下的贯彻情势很low,可是本人时期又没悟出好的措施,不知晓我们有没有好的艺术?

            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。

输出缓存Output caching

优化API接口

有二个API接口通常卡顿,而且很不安宁,快的时候2~3秒,慢的时候10秒去了。

接口必要:依照社区ID获取减价券记录。

分析:

  • 担当给API接口提供数据的种类中,紧缺许多目录,存在诸多慢查询视图。
  • 原先的LINQ完成情势是在内部存款和储蓄器中分页,响应速度太慢。
  • 出现请求的事态下,财富占用。

优化思路:

  数据缓存Data caching

壹 、使用缓存

同3个社区的人在同如今间所看到的降价券记录应当是相同的,而且大家应该允许脏读,大家在12306上面买高铁票的时候,平日也会看到显示有票,可是下单又从不了,或然是采取了缓存,那么我们那里其实同样的能够行使缓存来缓解并发难题。

在WebAPI下边加缓存,那么又分为客户端缓存和服务器缓存。而我们知道,在ASP.NET
WebForm和ASP.NET
MVC中都是有页面输出缓存的,而在WebAPI中暗许没有,从NuGet上边下载WebApi.OutputCache.V2,然后再API接口上添加 

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

小编这里无法直接选拔服务器输出缓存,那是因为不可能捕获缓存变量参数。因为大家API接口的伏乞参数是string
appParam,字符串类型的,它是四个json对象进过base63人编码,然后再进过url编码生成的字符串。

我们不得不解析后,获取社区ID,然后依照社区ID来安装缓存,把社区ID+
pageIndex就视作缓存的Key,考虑到须求缓存的数据量极小,那里自身直接使用.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. 输出缓存(Output Caching)

二 、改为存储进度完成

因为这几个接口的事情逻辑相比复杂,从前的Linq代码写了好长一大串,获取的记录数很多,而且照旧在内部存款和储蓄器中开始展览分页完成,所以笔者将原来的LINQ完毕代码修改为分页存款和储蓄进度实现。

积存进程代码如下:

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

那边要求留意的是,存款和储蓄执行是,先关闭计数,set nocount on;,然后再打开set
nocount off;,那样能够荣升质量。还有正是运用WITH ( NOLOCK
)允许脏读,升高查询效能。

此间境遇多个很古怪的标题,作者使用exec
sp_executesql
@strSql,N’….’的章程来施行是尚未难点的,而一旦自身利用拼接sql的措施,会报错,因为sql字符串被截断了,只截取到了6000个字符长度,固然作者把字符串变量长度设置为nvarchar(max)也没用。

分页情势使用Sqlserver贰零壹壹以上版本才支撑的长足形式:offset … FETCH NEXT
…ROWS ONLY

原先Linq的执行时间测试:

图片 6BLW.png)图片 7

本身修改为存款和储蓄进程之后的实施时间测试:

图片 8

特性差异11分引人注目。

  使用输出缓存,你能够缓存最终输出的HTML页面,当相同的页面重新呼吁的时候,ASP.NET不会再实施页面包车型地铁生命周期和血脉相通代码而是径直利用缓存的页面,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秒内一律的呼吁都会一向运用缓存的页面。当缓存过期后ASP.NET会再也实施页面代码并且为下贰个60秒创造二个新的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(); 
}

   在这么些例子中页面将被缓存20秒。

  因此询问字符串缓存(Cache by Query String )

  在实质上选择中页面往往会依照局部参数动态的改变页面的始末。倘使您的页面是经过查询字符串来获取音讯的,你可以依照查询字符串很简单的缓存页面包车型地铁例外拷贝。VarByParam=”None”钦点ASP.NET只存款和储蓄缓存页面包车型客车3个正片。VarByParam=”*”
钦点ASP.NET遵照分歧的询问字符串存款和储蓄差别的缓存页面。

<%@ 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为每3个ID都存储了单身的缓存页面。那种办法会有一部分难题便是当查问字符串范围很广的时候。

  那些时候大家能够在VarByParam
属性中钦定主要的询问字符串变量的名字,如下:

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

 

  那样,ASP.NET可以遵照id” or “langid”来缓存差异的缓存版本。

  自定义缓存(Custom Caching)

  你也足以创建自定义的主次来缓存页面。ASP.net提供了一种很便捷的法门来成立自定义缓存,使用VarByCustom属性钦命自定义缓存类型的名字。

  你还要创造为缓存生成自定义字符串的情势,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); 
  } 
  }

 

  这么些法子必须写在global.asax文件中。ASP.NET使用该格局再次回到的字符串来促成缓存,假使那些主题在不相同的请求中回到相同的字符串,ASP.NET就会利用缓存的页面,不然就会变卦新的缓存版本。

  上面包车型地铁事例中GetVaryByCustomString()方法依据浏览器的名字创办缓存字符串,ASP.NET会依照区别的浏览器请求创设不一样版本的缓存。

  控件缓存(Control Cache )

  上面包车型客车缓存技术能够让你很简单的缓存整个页面,如若要缓存内定控件的剧情,能够通过点名VaryByControl
属性来形成。

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

 

  上边代码ASP.NET将会缓存MyControl_1控件20分钟。假设要依照局地属性值来缓存控件只需求将OutPutCache指令参预*.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根据控件中宣称的EmployeeID属性来创立区别版本的缓存。

  在 .ascx.cs 文件加入EmplyeeID属性为ASP.NET 缓存使用。

  在页面中加进控件并且安装 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能够布置缓存相关的装置,

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

 

   你能够由此安装 CacheProfile=”ProfileName” 属性 来使用方面包车型大巴安顿:

  %@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。你能够将一部分消耗费时间间的条款参加到2个指标缓存集合中,以键值的办法存款和储蓄。

  Cache[“Name”] = data;

  大家得以由此使用Cache.Insert()方法来安装缓存的逾期,优先级,信赖项等。

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

  ASP.NET允许你设置3个万万过期时间或滑动过期时光,但无法而且选用。

  缓存重视项Cache dependency

  缓存注重项使缓存注重于任何财富,当注重项改成时,缓存条目项将自动从缓存中移除。缓存依赖项能够是应用程序的
Cache 中的文件、目录或与其余对象的键。若是文件或目录更改,缓存就会晚点。

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

 

  上面包车型大巴事例“Date2”缓存对象依赖“Date1”缓存条目,当 “Date1”
对象过期后“Date2” 将会自行过期。CacheDependency(null,
cacheKeys)中的第三个参数为空是由于大家只监视缓存键的更动意况。

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

  ASP.NET允许我们写二个回调函数,当缓存条目从缓存中移除的时候接触。还足以设置缓存条目标预先级。

  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”); 
  } 
  }

 

  例子中成立了“Date1” 和 “Date2”缓存。“Date1”
在20秒后过期“Date2”为40秒。但是出于我们报了名了移除的回调函数,当“Date1”
或 “Date2”个中1个逾期都会履行CachedItemRemoveCallBack
方法,在那些艺术中移除了三个缓存条目,ASP.NET还提供了处理缓存条目更新时的回调函数CacheItemUpdateCallback

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