.Net Core使用Redis

一.准备　　

　　在.Net Core项目中使用StackExChange.Redis来使用Redis，这里通过Nuget去安装相关的包。安装完如下图。

二.配置

　　在appsettings.json中配置Redis的相关信息。一般需要配置连接地址、实例名、哪个DB、密码。

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  },
  "AllowedHosts": "*",
  "Redis": {
    "Default": {
      "Connection": "127.0.0.1:6379",
      "InstanceName": "local",
      "DefaultDB": 0,
      "Password": "12345"
    }
  }
}

三.使用

　　在Startup.cs中添加redis的依赖。

public Startup(IConfiguration configuration)
{
    Configuration = configuration;
}

public IConfiguration Configuration { get; }

// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
    //redis缓存
    var section = Configuration.GetSection("Redis:Default");
    //连接字符串
    string _connectionString = section.GetSection("Connection").Value;
    //实例名称
    string _instanceName = section.GetSection("InstanceName").Value;
    //默认数据库 
    int _defaultDB = int.Parse(section.GetSection("DefaultDB").Value ?? "0");
    //密码
    string _password = section.GetSection("Password").Value;
    //注入容器
    services.AddSingleton(new RedisHelper(_connectionString, _instanceName, _password, _defaultDB));
}

　　Redis使用类的定义。

public class RedisHelper : IDisposable
{
    //连接字符串
    private string _connectionString;
    //实例名称
    private string _instanceName;
    //密码
    private string _password;
    //默认数据库
    private int _defaultDB;
    private ConcurrentDictionary<string, ConnectionMultiplexer> _connections;
    public RedisHelper(string connectionString, string instanceName, string password, int defaultDB = 0)
    {
        _connectionString = connectionString;
        _instanceName = instanceName;
        _password = password;
        _defaultDB = defaultDB;
        _connections = new ConcurrentDictionary<string, ConnectionMultiplexer>();
    }

    /// <summary>
    /// 获取ConnectionMultiplexer
    /// </summary>
    /// <returns></returns>
    private ConnectionMultiplexer GetConnect()
    {
        return _connections.GetOrAdd(_instanceName, p => ConnectionMultiplexer.Connect(_connectionString + ",password=" + _password));
    }

    /// <summary>
    /// 获取数据库
    /// </summary>
    /// <param name="configName"></param>
    /// <param name="db">默认为0：优先代码的db配置，其次config中的配置</param>
    /// <returns></returns>
    public IDatabase GetDatabase()
    {
        return GetConnect().GetDatabase(_defaultDB);
    }

    public IServer GetServer(string configName = null, int endPointsIndex = 0)
    {
        var confOption = ConfigurationOptions.Parse(_connectionString);
        return GetConnect().GetServer(confOption.EndPoints[endPointsIndex]);
    }

    public ISubscriber GetSubscriber(string configName = null)
    {
        return GetConnect().GetSubscriber();
    }

    public void Dispose()
    {
        if (_connections != null && _connections.Count > 0)
        {
            foreach (var item in _connections.Values)
            {
                item.Close();
            }
        }
    }
}

　　在接口中注入依赖去使用。

[Route("api/test")]
[ApiController]
public class TestController : ControllerBase
{
    private readonly IDatabase _redis;
    public TestController(RedisHelper client)
    {
        //创建Redis连接对象
        _redis = client.GetDatabase();
    }

    //格式 string
    //cmd: getset key value
    [Route("set")]
    [HttpPost]
    public string Set(string key, string value)
    {
        string result;
        // 往Redis里面存入数据
        if (_redis.StringSet(key, value))
        {
            result = "成功";
        }
        else
        {
            result = "失败";
        }
        return result;
    }

    //格式 string
    //cmd: get key
    [Route("get")]
    [HttpGet]
    public string Get(string key)
    {
        // 从Redis里面取数据
        string value = _redis.StringGet(key);
        return value;
    }

    //格式 hash
    //cmd: hset key field value
    [Route("hset")]
    [HttpPost]
    public string HSet(string key, string hashField, string value)
    {
        string result;

        // 往Redis里面存入数据
        if (_redis.HashSet(key, hashField, value))
        {
            result = "成功";
        }
        else
        {
            result = "失败";
        }
        return result;
    }

    //格式 hash
    //cmd: hget key field
    [Route("hget")]
    [HttpGet]
    public string HGet(string key, string hashField)
    {
        // 从Redis里面取数据
        string value = _redis.HashGet(key, hashField);
        return value;
    }
}

　　IDataBase接口定义了方法，基本包括了Redis操作的各个方法，可以参考Redis的命令行方法来查找对应的方法。

　　Redis命令可以参考这篇 https://www.cnblogs.com/shadoll/p/14388289.html

四.总结

　　1.在.Net Core安装Redis使用的StackExChange.Redis包，确保Redis服务处于正常启动状态，配置连接项即可。

　　2.熟悉Redis的命令行操作，就可以大致了解StackExChange.Redis的使用方法（它底层应该也是执行Redis的命令操作）。