Redis实战 - 1.String和计数器
在.NET Core 项目中操练String
使用 StackExchange.Redis 访问 Redis
static void Main(string[] args)
{
using (ConnectionMultiplexer redis = ConnectionMultiplexer.Connect("localhost:6379"))
{
IDatabase db = redis.GetDatabase();
db.StringSet("name", "Michal Jackson");
string name = db.StringGet("name");
Console.WriteLine(name); //结果：Michal Jackson
db.StringSet("age", "11");
//incr 自增
db.StringIncrement("age");
RedisValue age = db.StringGet("age");
Console.WriteLine(age);//结果：12
//incrby 指定增量
age = db.StringIncrement("age", 5);
Console.WriteLine(age);//结果：17
//decr 自减
age = db.StringDecrement("age");
Console.WriteLine(age);//结果：16
//decrby 指定减量
age = db.StringDecrement("age", 5);
Console.WriteLine(age);//结果：11
//mset 设置多个值
db.StringSet(new KeyValuePair<RedisKey, RedisValue>[]
{
new KeyValuePair<RedisKey, RedisValue>("aa", "aa"),
new KeyValuePair<RedisKey, RedisValue>("bb", "bb"),
new KeyValuePair<RedisKey, RedisValue>("cc", "5"),
});
//mget 取多个值
var values = db.StringGet(new RedisKey[] { "aa", "bb", "cc" });
foreach (RedisValue redisValue in values)
{
Console.Write(redisValue + ",");
}
//结果：aa,bb,5
//exists 是否存在
db.StringSet("name1", "Dave1");
bool existsResult = db.KeyExists("name1");
Console.WriteLine(existsResult); //结果：true
//del 删除
bool delResult = db.KeyDelete("name1");
Console.WriteLine(delResult); //结果：true
existsResult = db.KeyExists("name1");
Console.WriteLine(existsResult); //结果：false
//type 判断类型
db.StringSet("name2", "Dave2");
var typeOfValue = db.KeyType("name2");
Console.WriteLine(typeOfValue); //String
//expire 过期时间
db.StringSet("name3", "Dave3");
db.KeyExpire("name3", TimeSpan.FromSeconds(5));
RedisValue value = db.StringGet("name3");
Console.WriteLine(value); //Dave3
Console.WriteLine("此处等待6秒...");
Thread.Sleep(6 * 1000);
value = db.StringGet("name3"); //啥也没有..
Console.WriteLine(value);
//ex 设置key直接设置有效期
db.StringSet("name4","Dave4", TimeSpan.FromSeconds(5));
RedisValue value4 = db.StringGet("name4");
Console.WriteLine(value4); //Dave4
Console.WriteLine("此处等待6秒...");
Thread.Sleep(6 * 1000);
value4 = db.StringGet("name4"); //啥也没有..
Console.WriteLine(value4);
//ttl 查看过期时间
db.StringSet("name6","Dave6", TimeSpan.FromSeconds(5));
for (int i = 1; i < 7; i++)
{
Thread.Sleep( 1000);
RedisValue valueTTL = db.StringGet("name6");
var ttl = db.KeyTimeToLive("name6");
if (ttl==null)
{
Console.WriteLine($"{i}秒过后：Dave6已过期");
}
else
{
Console.WriteLine($"{i}秒过后：{valueTTL}还能存活{ttl}秒");
}
}
// 1秒过后：Dave6还能存活00：00：03.9970000秒
// 2秒过后：Dave6还能存活00：00：02.9040000秒
// 3秒过后：Daue6还能存活00：00：01.9040000秒
// 4秒过后：Dave6还能存活00：00：00.9030000秒
// 5秒过后：Dave6已过期
// 6秒过后：Daue6已过期
}
Console.ReadKey();
}
1.string值写到前台，取RedisValue
先 Startup.cs 注入 IConnectionMultiplexer
services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
services.AddSingleton<IConnectionMultiplexer>(ConnectionMultiplexer.Connect("localhost:6379"));
在 HomeController.cs
public class HomeController : Controller
{
private readonly IConnectionMultiplexer _redis;
private readonly IDatabase _db;
public HomeController(IConnectionMultiplexer redis)
{
_redis = redis;
_db = _redis.GetDatabase();
}
public IActionResult Index()
{
_db.StringSet("fullname", "Michael Jackson");
var name = _db.StringGet("fullname");
return View("Index", name);
}
}
视图 Index
@model StackExchange.Redis.RedisValue
<div class="text-center">
<h1 class="display-4"> Welcome:@Model </h1>
<p>Learn about <a href="https://docs.microsoft.com/aspnet/core">building Web apps with ASP.NET Core</a>.</p>
</div>
2.计数器
2.1 视图组件 ViewComponent
创建 CounterViewComponent 类
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.AspNetCore.Mvc;
using System.Threading.Tasks;
using StackExchange.Redis;
namespace RedisToEsay.ViewComponents
{
public class CounterViewComponent : ViewComponent
{
private readonly IDatabase _db;
public CounterViewComponent(IConnectionMultiplexer redis)
{
_db = redis.GetDatabase();
}
public async Task<IViewComponentResult> InvokeAsync()
{
string controller = RouteData.Values["controller"].ToString();
string action = RouteData.Values["action"].ToString();
if (!string.IsNullOrWhiteSpace(controller) && !string.IsNullOrWhiteSpace(action))
{
var pageId = $"{controller}-{action}";
await _db.StringIncrementAsync(pageId);
var count = _db.StringGet(pageId);
return View("Default", pageId + ":" + count);
}
throw new Exception("can't get pageId");
}
}
}
创建 Default 视图
@model string
<h4>@Model</h4>
然后在Shared_Layout.cshtml 调用
<div>
@await Component.InvokeAsync("Counter")
</div>
报错：Defualt 创建的位置不对
An unhandled exception occurred while processing the request.
InvalidOperationException: The view 'Components/Counter/Default' was not found. The following locations were searched:
/Views/Home/Components/Counter/Default.cshtml
/Views/Shared/Components/Counter/Default.cshtml
/Pages/Shared/Components/Counter/Default.cshtml
所以创建的位置在
/Views/Shared/Components/Counter/Default.cshtml
参考：
草根专栏，Redis in .NET Core 入门：(2) String
杨旭(Video)，Redis in ASP.NET Core 1. 计数器
