ASP.NET结合Redis实现分布式缓存

 

最近一个项目ASP.NET+MySQL

有的网页打开初始化的查询须要10秒甚至更久，用户体验极差，并且并发量变大的时候网站容易崩溃

后来想了两种解决方案都不是太满意

一、数据库里建一张缓存表，后台做业定时去更新这张表，每次网页打开就能够直接从缓存表里查询

二、用户第一次打开网站将数据已文件的形式缓存到服务器上，下次直接从文件中读取数据

最后决定用Redis分布式缓存实现

Redis是在Linux系统上安装的，不过也有Windows版本的安装包，我是将它设置成了服务

下载地址 https://github.com/MicrosoftArchive/redis/releases

解压后目录结构以下

以管理员方式打开命令行，跳转到Redis解压的目录下，执行命令 redis-server --service-install redis.windows.conf

会提示服务安装成功

打开计算机管理->服务，已经能够看到Redis服务了，将它设置为开机自动运行

接下来，要使用ServiceStack.Redis在C#中操做Redis

能够经过Nuget安装，也能够到网上下载这个类库

最新版本的版本(好像是5.0)是收费的，免费版一个小时以内有缓存6000次的限制。

若是须要破解版能够联系我QQ 22378930

固然也可使用比较旧的ServiceStack版本，好比3.0

首先添加ServiceStack的引用

ServiceStack.Common.dll

ServiceStack.Interfaces.dll

ServiceStack.Redis.dll

ServiceStack.Text.dll

添加引用后，在web.config中添加一些配置

 <appSettings>
    <add key="WriteServerList" value="127.0.0.1:6379" />
    <add key="ReadServerList" value="127.0.0.1:6379" />
    <add key="MaxWritePoolSize" value="60" />
    <add key="MaxReadPoolSize" value="60" />
    <add key="AutoStart" value="true" />
    <add key="LocalCacheTime" value="1800" />
    <add key="RecordeLog" value="false" />
  </appSettings>

配置文件操做类

 public class RedisConfigInfo
    {
        public static string WriteServerList = ConfigurationManager.AppSettings["WriteServerList"];
        public static string ReadServerList = ConfigurationManager.AppSettings["ReadServerList"];
        public static int MaxWritePoolSize = Convert.ToInt32(ConfigurationManager.AppSettings["MaxWritePoolSize"]);
        public static int MaxReadPoolSize = Convert.ToInt32(ConfigurationManager.AppSettings["MaxReadPoolSize"]);
        public static int LocalCacheTime = Convert.ToInt32(ConfigurationManager.AppSettings["LocalCacheTime"]);
        public static bool AutoStart = ConfigurationManager.AppSettings["AutoStart"].Equals("true") ? true : false;
    }

链接Redis,以及其余的一些操做类

public class RedisManager
    {
        private static PooledRedisClientManager prcm;

        /// <summary>
        /// 建立连接池管理对象
        /// </summary>
        private static void CreateManager()
        {
            string[] writeServerList = SplitString(RedisConfigInfo.WriteServerList, ",");
            string[] readServerList = SplitString(RedisConfigInfo.ReadServerList, ",");

            prcm = new PooledRedisClientManager(readServerList, writeServerList,
                             new RedisClientManagerConfig
                             {
                                 MaxWritePoolSize = RedisConfigInfo.MaxWritePoolSize,
                                 MaxReadPoolSize = RedisConfigInfo.MaxReadPoolSize,
                                 AutoStart = RedisConfigInfo.AutoStart,
                             });
        }

        private static string[] SplitString(string strSource, string split)
        {
            return strSource.Split(split.ToArray());
        }

        /// <summary>
        /// 客户端缓存操做对象
        /// </summary>
        public static IRedisClient GetClient()
        {
            if (prcm == null)
                CreateManager();

            return prcm.GetClient();
        }
        /// <summary>
        /// 缓存默认24小时过时
        /// </summary>
        public static TimeSpan expiresIn = TimeSpan.FromHours(24);
        /// <summary>
        /// 设置一个键值对，默认24小时过时
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key"></param>
        /// <param name="value"></param>
        /// <param name="redisClient"></param>
        /// <returns></returns>
        public static bool Set<T>(string key, T value, IRedisClient redisClient)
        {

            return redisClient.Set<T>(key, value, expiresIn);
        }

        /// <summary>
        /// 将某类数据插入到list中
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key">通常是BiaoDiGuid</param>
        /// <param name="item"></param>
        /// <param name="redisClient"></param>
        public static void Add2List<T>(string key, T item, IRedisClient redisClient)
        {
            var redis = redisClient.As<T>();
            var list = redis.Lists[GetListKey(key)];
            list.Add(item);
        }

        /// <summary>
        /// 获取一个list
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key"></param>
        /// <param name="redisClient"></param>
        /// <returns></returns>
        public static IRedisList<T> GetList<T>(string key, IRedisClient redisClient)
        {
            var redis = redisClient.As<T>();
            return redis.Lists[GetListKey(key)];
        }

        public static string GetListKey(string key, string prefix = null)
        {
            if (string.IsNullOrEmpty(prefix))
            {
                return "urn:" + key;
            }
            else
            {
                return "urn:" + prefix + ":" + key;
            }
        }
    }

下面咱们来测试一下是否可以成功读取Redis缓存

 <form id="form1" runat="server">
    <div>
        <asp:Label runat="server" ID="lbtest"></asp:Label>
        <asp:Button runat="server" ID ="btn1" OnClick="btn1_Click" Text="获取测试数据"/>
    </div>
    </form>

 protected void btn1_Click(object sender, EventArgs e)
        {
            string UserName;
            //读取数据，若是缓存存在直接从缓存中读取，不然从数据库读取而后写入redis
            using (var redisClient = RedisManager.GetClient())
            {
                UserName = redisClient.Get<string>("UserInfo_123");
                if (string.IsNullOrEmpty(UserName)) //初始化缓存
                {
                    //TODO 从数据库中获取数据，并写入缓存
                    UserName = "张三";
                    redisClient.Set<string>("UserInfo_123", UserName, DateTime.Now.AddSeconds(10));
                    lbtest.Text = "数据库数据：" + "张三";
                    return;
                }
                lbtest.Text = "Redis缓存数据：" + UserName;
            }
        }

首次访问缓存中数据不存在，获取数据并写入缓存，并设定有效期10秒

10秒内再次访问读取缓存中数据