之前有写过一篇介绍c#操作redis的文章 http://www.cnblogs.com/axel10/p/8459434.html ,这篇文章中的案例使用了StringIncrement来实现了高并发情况下key值的稳定增加,但如果要用锁的方式而不是StringIncrement方法,那该怎么做呢?
LockTake涉及到三个参数:key,token和TimeSpan,分别表示redis数据库中该锁的名称、锁的持有者标识和有效时间。下面将用一个多线程增加key值的案例来演示LockTake/LockRelease的用法。
using StackExchange.Redis; using StackExchange.Redis.Extensions.Core; using StackExchange.Redis.Extensions.Core.Configuration; using StackExchange.Redis.Extensions.Newtonsoft; using System; using System.Threading; namespace RedisTest { class Program { static RedisValue Token = Environment.MachineName; static RedisKey Key = "lock"; static void Ins() { Thread thread = new Thread(() => { for (int i = 0; i < 100; i++) { if (client.Database.LockTake(Key, Token, TimeSpan.MaxValue)) //key表示的是redis数据库中该锁的名称,不可重复。 Token用来标识谁拥有该锁并用来释放锁。TimeSpan表示该锁的有效时间。 { try { int key = client.Get<int>("key"); client.Add("key", key + 10); } catch (Exception e) { Console.WriteLine(e); throw; } finally { client.Database.LockRelease(Key, Token); } } else { Console.WriteLine("locking"); while (!TryAgain(10)) { Thread.Sleep(1); } } } }); thread.Start(); } private static StackExchangeRedisCacheClient client; static void Main(string[] args) { var redisConfiguration = new RedisConfiguration() //配置 { Hosts = new RedisHost[] { new RedisHost() {Host = "127.0.0.1", Port = 6379} } }; client = new StackExchangeRedisCacheClient(new NewtonsoftSerializer(), redisConfiguration); client.Add("key", 0); for (int j = 0; j < 10; j++) { Ins(); } Thread.Sleep(2000); int i = client.Get<int>("key"); Console.WriteLine(i); Console.ReadKey(); } static bool TryAgain(int value) { if (client.Database.LockTake(Key, Token, TimeSpan.MaxValue)) { try { int key = client.Get<int>("key"); client.Add("key", key + value); } catch (Exception e) { Console.WriteLine(e); throw; } finally { client.Database.LockRelease(Key, Token); } return true; } else { return false; } } } }