1、RabbitMQ.MessageProducer

新建类 **PriorityQueue**

csharp
public static void Show()
{
    var factory = new ConnectionFactory()
    {
        HostName = "localhost",
        UserName = "guest",
        Password = "guest"
    };

    using var connection = factory.CreateConnection();
    using var channel = connection.CreateModel();

    channel.QueueDeclare("PriorityQueue", true, false, false, new Dictionary<string, object>()
    {
        // 指定队列要支持优先级队列
        { "x-max-priority",10 }
    });
    // 声明交换机
    channel.ExchangeDeclare("PriorityQueueExchange", ExchangeType.Direct, true, false, null);
    // 绑定交换机和队列
    channel.QueueBind("PriorityQueue", "PriorityQueueExchange", "PriorityKey");
    // 一些待发送的消息
    string[] questionList = { "vip1 来请教", "甲 同学来请教", "乙 同学来请教", "丙 同学来请教", "丁 同学来请教", "vip2 来请教" };

    var props = channel.CreateBasicProperties();
    // 设置持久化
    props.DeliveryMode = 2;
    foreach (var msg in questionList)
    {
        if (msg.StartsWith("vip"))
        {
            // 设置优先级
            props.Priority = 9;
            channel.BasicPublish("PriorityQueueExchange", "PriorityKey", props, Encoding.UTF8.GetBytes(msg));
        }
        else
        {
            props.Priority = 1;
            channel.BasicPublish("PriorityQueueExchange", "PriorityKey", props, Encoding.UTF8.GetBytes(msg));
        }
        Console.WriteLine($"{msg} 已发送");
    }

    Console.ReadLine();

}

2、RabbitMQ.MessageConsumer01

新建类 **PriorityQueue**

csharp
public static void Show()
{
    var factory = new ConnectionFactory()
    {
        HostName = "localhost",
        UserName = "guest",
        Password = "guest"
    };

    using var connection = factory.CreateConnection();
    using var channel = connection.CreateModel();

    var consumer = new EventingBasicConsumer(channel);
    consumer.Received += (model, ea) =>
    {
        Console.WriteLine(Encoding.UTF8.GetString(ea.Body.ToArray()));
    };
    Console.WriteLine("消费者准备就绪。。。");
    // 处理消息
    channel.BasicConsume("PriorityQueue", true, consumer);

    Console.ReadLine();
}

3、注意

优先级

csharp
// 声明的队列需要加入参数 x-max-priority
var props = channel.CreateBasicProperties();
// 值越大，优先级越高
props.Priority = 9;

持久化

csharp
// 在声明队列和交换机时需要将 durable 设置为 true
var props = channel.CreateBasicProperties();
// 设置持久化
props.DeliveryMode = 2;