很简单的代码，看注释

class Program
{
    private static ManualResetEvent _manualResetEvent = new ManualResetEvent(false);
    // 参数值1，约束集合的大小。当_messageQueue.Add时大小已经为1时，Add会阻塞。可注释掉Thread.Sleep(5000);尝试
    //private static BlockingCollection<string> _messageQueue = new BlockingCollection<string>(1);
    // 不限大小
    private static BlockingCollection<string> _messageQueue = new BlockingCollection<string>();

    static void Main(string[] args)
    {
        startProducer();
        startConsumer();

        _manualResetEvent.WaitOne();
    }

    /// <summary>
    /// 生产者
    /// </summary>
    private static void startProducer()
    {
        var ProducerThread = new Thread(() =>
        {
            while (true)
            {
                var message = Console.ReadLine();
                if (message == "exit")
                {
                    _manualResetEvent.Set();
                    return;
                }

                Console.WriteLine($"生产者发出消息: {message}");

                _messageQueue.Add(message);
            }
        });
        ProducerThread.IsBackground = true;
        ProducerThread.Start();
    }

    /// <summary>
    /// 消费者
    /// </summary>
    private static void startConsumer()
    {
        var consumerThread = new Thread(() =>
        {
            // 这里会一直执行下去, 有消息则会处理
            foreach (var message in _messageQueue.GetConsumingEnumerable())
            {
                Console.WriteLine($"消费者收到消息:{message}");
                //Thread.Sleep(5000);
            }
        });
        consumerThread.IsBackground = true;
        consumerThread.Start();
    }
}