给出 dotnet cor 中使用ZooKeeperNetEx实现分布式锁的实现

为了实现基于ZooKeeper的分布式锁，您可以使用ZooKeeperNetEx nuget包安装ZooKeeper客户端，并使用以下代码实现分布式锁：

using System;
using System.Threading.Tasks;
using org.apache.zookeeper;

namespace ZooKeeperLock
{
    public class DistributedLock : IDisposable
    {
        private readonly ZooKeeper _zooKeeper;
        private readonly string _lockPath;
        private string _currentLockPath;

        public DistributedLock(string connectionString, string lockPath)
        {
            _zooKeeper = new ZooKeeper(connectionString, TimeSpan.FromSeconds(10), null);
            _lockPath = lockPath;
        }

        public async Task AcquireLock()
        {
            while (true)
            {
                try
                {
                    _currentLockPath = await _zooKeeper.createAsync(_lockPath + "/lock-", null, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL_SEQUENTIAL);
                    var locks = await _zooKeeper.getChildrenAsync(_lockPath, false);
                    var currentSeq = long.Parse(_currentLockPath.Substring(_lockPath.Length + "/lock-".Length));
                    var minSeq = long.MaxValue;
                    foreach (var lockNode in locks.Children)
                    {
                        var seq = long.Parse(lockNode.Substring("lock-".Length));
                        if (seq < minSeq)
                        {
                            minSeq = seq;
                        }
                    }
                    if (currentSeq == minSeq)
                    {
                        return;
                    }
                    await _zooKeeper.deleteAsync(_currentLockPath);
                }
                catch (KeeperException.NoNodeException)
                {
                    await _zooKeeper.createAsync(_lockPath, null, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
                }
            }
        }

        public void Dispose()
        {
            _zooKeeper?.deleteAsync(_currentLockPath);
            _zooKeeper?.closeAsync();
        }
    }
}

您可以使用以下方式使用分布式锁：

using System;

namespace ZooKeeperLock
{
    class Program
    {
        static void Main(string[] args)
        {
            using (var lockObject = new DistributedLock("localhost:2181", "/mylock"))
            {
                lockObject.AcquireLock().Wait();
                Console.WriteLine("This code is protected by distributed lock.");
                Console.ReadLine();
            }
        }
    }
}

请注意，此实现基于ZooKeeper 3.4.0版本，可以使用其他版本的ZooKeeper和ZooKeeperNetEx进行修改。