这篇文章让我们来说下 StackExchange.Redis的使用及帮助类

首先在windows上安装redis 在上边连接中有教程

1.创建net core项目

2.在包管理器中安装StackExchange.Redis的Nuget包，如下图：

4.在appsettings.json中添加connection连接字符串：(redis连接字符串)

5.然后新建一个RedisClient.cs 帮助类，简单封装了一下redis的读写操作

using Microsoft.Extensions.Configuration;

using Newtonsoft.Json;

using StackExchange.Redis;

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace Core.Common

{

/// <summary>

/// RedisClient.cs 帮助类

/// </summary>

public static class RedisClient

{

static ConnectionMultiplexer redis = null;

static IDatabase db = null;

public static void InitConnect(IConfiguration Configuration)

{

try

{

var RedisConnection = Configuration.GetConnectionString("RedisConnectionString");

redis = ConnectionMultiplexer.Connect(RedisConnection);

db = redis.GetDatabase();

}

catch (Exception ex)

{

Console.WriteLine(ex.Message);

redis = null;

db = null;

}

}

#region String

/// <summary>

/// 保存单个key value

/// </summary>

/// <param name="value">保存的值</param>

/// <param name="expiry">过期时间</param>

public static bool SetStringKey(string key, string value, TimeSpan? expiry = default(TimeSpan?))

{

return db.StringSet(key, value, expiry);

}

/// <summary>

/// 获取单个key的值

/// </summary>

public static RedisValue GetStringKey(string key)

{

return db.StringGet(key);

}

/// <summary>

/// 获取一个key的对象

/// </summary>

public static T GetStringKey<T>(string key)

{

if (db == null)

{

return default;

}

var value = db.StringGet(key);

if (value.IsNullOrEmpty)

{

return default;

}

return JsonConvert.DeserializeObject<T>(value);

}

/// <summary>

/// 保存一个对象

/// </summary>

/// <param name="obj"></param>

public static bool SetStringKey<T>(string key, T obj, TimeSpan? expiry = default(TimeSpan?))

{

if (db == null)

{

return false;

}

string json = JsonConvert.SerializeObject(obj);

return db.StringSet(key, json, expiry);

}

#endregion

/// <summary>

/// 将一个泛型List添加到缓存中

/// </summary>

/// <typeparam name="T">泛型T</typeparam>

/// <param name="listkey">Key</param>

/// <param name="list">list</param>

/// <param name="db_index">数据库序号，不传默认为0</param>

/// <returns></returns>

public static bool addList<T>(string listkey, List<T> list, int db_index = 0)

{

if (db == null)

{

return false;

}

var value = JsonConvert.SerializeObject(list);

return db.StringSet(listkey, value);

}

/// <summary>

/// 通过指定Key值获取泛型List

/// </summary>

/// <typeparam name="T">泛型T</typeparam>

/// <param name="listkey">Key</param>

/// <param name="db_index">数据库序号，不传默认为0</param>

/// <returns></returns>

public static List<T> getList<T>(string listkey, int db_index = 0)

{

//var db = redis.GetDatabase(db_index);

if (db == null)

{

return new List<T>();

}

if (db.KeyExists(listkey))

{

var value = db.StringGet(listkey);

if (!string.IsNullOrEmpty(value))

{

var list = JsonConvert.DeserializeObject<List<T>>(value);

return list;

}

else

{

return new List<T>();

}

}

else

{

return new List<T>();

}

}

public static bool getKeyExists(string listkey, int db_index = 0)

{

if (db == null)

{

return false;

}

if (db.KeyExists(listkey))

{

return true;

}

else

{

return false;

}

}

/// <summary>

/// 删除指定List<T>中满足条件的元素

/// </summary>

/// <param name="listkey">Key</param>

/// <param name="func">lamdba表达式</param>

/// <param name="db_index">数据库序号，不传默认为0</param>

/// <returns></returns>

public static bool delListByLambda<T>(string listkey, Func<T, bool> func, int db_index = 0)

{

if (db == null)

{

return false;

}

if (db.KeyExists(listkey))

{

var value = db.StringGet(listkey);

if (!string.IsNullOrEmpty(value))

{

var list = JsonConvert.DeserializeObject<List<T>>(value);

if (list.Count > 0)

{

list = list.SkipWhile<T>(func).ToList();

value = JsonConvert.SerializeObject(list);

return db.StringSet(listkey, value);

}

else

{

return false;

}

}

else

{

return false;

}

}

else

{

return false;

}

}

/// <summary>

/// 获取指定List<T>中满足条件的元素

/// </summary>

/// <param name="listkey">Key</param>

/// <param name="func">lamdba表达式</param>

/// <param name="db_index">数据库序号，不传默认为0</param>

/// <returns></returns>

public static List<T> getListByLambda<T>(string listkey, Func<T, bool> func, int db_index = 0)

{

if (db == null)

{

return new List<T>();

}

if (db.KeyExists(listkey))

{

var value = db.StringGet(listkey);

if (!string.IsNullOrEmpty(value))

{

var list = JsonConvert.DeserializeObject<List<T>>(value);

if (list.Count > 0)

{

list = list.Where(func).ToList();

return list;

}

else

{

return new List<T>();

}

}

else

{

return new List<T>();

}

}

else

{

return new List<T>();

}

}

}

}

6.在Startup.cs入口中 初始化RedisClient 的连接：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Threading.Tasks;

using Microsoft.AspNetCore.Builder;

using Microsoft.AspNetCore.Hosting;

using Microsoft.AspNetCore.HttpsPolicy;

using Microsoft.AspNetCore.Mvc;

using Microsoft.Extensions.Configuration;

using Microsoft.Extensions.DependencyInjection;

using Microsoft.Extensions.Logging;

using Microsoft.Extensions.Options;

namespace CoreWebApiService

{

public class Startup

{

public Startup(IConfiguration configuration)

{

Configuration = configuration;

}

public IConfiguration Configuration { get; }

public void ConfigureServices(IServiceCollection services)

{

//初始化redis

RedisClient.InitConnect(Configuration);//*******

}

public void Configure(IApplicationBuilder app, IHostingEnvironment env)

{

if (env.IsDevelopment())

{

app.UseDeveloperExceptionPage();

}

else

{

app.UseHsts();

}

app.UseHttpsRedirection();

app.UseMvc();

}

}

}

7.最后，在Controller.cs中调用

using Core.Common;

using Core.Contract;

using Core.ViewEntity;

namespace CoreWebApiService.Controllers

{

[Route("api/[controller]")]

[ApiController]

public class RedisDemoController : Controller

{

private readonly IAccessService _iAccess;

public RedisDemoController(IAccessService iAccess)

{

_iAccess = iAccess;

}

/// <summary>

///若redis没有数据,则取数据并设置redis

/// </summary>

/// <param name="id"></param>

/// <returns></returns>

[HttpGet]

public ActionResult<string> Get(int id)

{

var redisResult = RedisClient.GetStringKey<int>("key1");

//若redis没有数据,则取数据并设置redis

if (redisResult == null || redisResult == 0)

{

Console.WriteLine("redisResult is empty");

RedisClient.SetStringKey("key1", id.ToString(),TimeSpan.FromDays(1)); //30秒过期

return id.ToString();

}

return redisResult.ToString();//有则直接返回

}

/// <summary>

/// 缓存中如果存在这个key返回查出的数据 如果不存在则写入缓存 查出数据后进行条件筛选和分页

/// </summary>

/// <param name="name">简称</param>

/// <param name="startIndex">开始索引</param>

/// <param name="limitedQuantity">限定数量</param>

/// <returns></returns>

[HttpPost]

public ActionResult GetList(string name, int startIndex, int limitedQuantity)

{

try

{

//缓存中如果存在这个key返回查出的数据 如果不存在则写入缓存 查出数据后进行条件筛选和分页

List<ContentUserViewEntity> list = null;

if (RedisClient.getKeyExists("listKey"))

{

list = RedisClient.getList<ContentUserViewEntity>("listKey")

}

else

{

Dictionary<string, string> paramers = new Dictionary<string, string>();

RedisClient.addList("listKey", GetContentUserByWhere(paramers));//插入key 和集合

list = RedisClient.getList<ContentUserViewEntity>("listKey");

}

if (!string.IsNullOrEmpty(name))

{

list = list.Where(x => x.Name.Contains(name)).ToList();

}

if (list.Count < limitedQuantity)

{

return Json(new { ok = true, msg = "sucess", data = list.GetRange(startIndex, list.Count) });

}

return Json(new { ok = true, msg = "sucess", data = list.GetRange(startIndex, limitedQuantity) });

}

catch (Exception ex)

{

return Json(new { ok = false, msg = ex.Message, data = "" });

}

}

private List<ContentUserViewEntity> GetContentUserByWhere(Dictionary<string, string> paramers)

{

try

{

#region 方法二

var entity = _iAccess.GetContentUserByWhere(paramers);

#endregion

return entity;

}

catch (Exception exp)

{

return null;

}

}

}

}

F5运行，输入：https://localhost:5001/api/values/100

返回100，此时redis中的数据库已经存入了 key1，100.

再次访问https://localhost:5001/api/values/99，还是会返回100，因为已经从redis中取数据了