溪客(编程代码)

exchange-topic

主题交换机，直连交换机的升级版，可以通过*号或#号模糊匹配队列

如下图所示，队列绑定到交换机时指定的routingKey是带有*号或者#号的，表示接收类似的routingKey

如果有两条队列匹配上，两条队列都会收到

例如，下面的三条队列，分别为A->agreements.eu.berlin.#，B->agreements.# ，C->agreements.eu.*.headstore

假如生产者指定的routingKey为agreements.eu.berlin，那么会匹配上A和B

示例代码：

var factory = new ConnectionFactory() { HostName = "localhost" };
using (var connection = factory.CreateConnection())
using (var channel = connection.CreateModel())
{
    // Topic类型的exchange, 名称 agreements
    channel.ExchangeDeclare(exchange: "agreements",
                            type: ExchangeType.Topic,
                            durable: true,
                            autoDelete: false,
                            arguments: null);

    // 创建berlin_agreements队列
    channel.QueueDeclare(queue: "berlin_agreements",
                            durable: true,
                            exclusive: false,
                            autoDelete: false,
                            arguments: null);

    //创建 all_agreements 队列
    channel.QueueDeclare(queue: "all_agreements",
                            durable: true,
                            exclusive: false,
                            autoDelete: false,
                            arguments: null);

    //创建 headstore_agreements 队列
    channel.QueueDeclare(queue: "headstore_agreements",
                            durable: true,
                            exclusive: false,
                            autoDelete: false,
                            arguments: null);

    //绑定 agreements --> berlin_agreements 使用routingkey:agreements.eu.berlin.#
    channel.QueueBind(queue: "berlin_agreements",
                        exchange: "agreements",
                        routingKey: "agreements.eu.berlin.#",
                        arguments: null);

    //绑定 agreements --> all_agreements 使用routingkey:agreements.#
    channel.QueueBind(queue: "all_agreements",
                        exchange: "agreements",
                        routingKey: "agreements.#",
                        arguments: null);

    //绑定 agreements --> headstore_agreements 使用routingkey:agreements.eu.*.headstore
    channel.QueueBind(queue: "headstore_agreements",
                        exchange: "agreements",
                        routingKey: "agreements.eu.*.headstore",
                        arguments: null);


    var message = "hello world";
    var body = Encoding.UTF8.GetBytes(message);
    var properties = channel.CreateBasicProperties();
    properties.Persistent = true;

    //发送消息到exchange :agreements ,使用routingkey: agreements.eu.berlin
    //agreements.eu.berlin 匹配  agreements.eu.berlin.# 和agreements.#
    //agreements.eu.berlin 不匹配  agreements.eu.*.headstore
    //最终次消息会路由到队里：berlin_agreements（agreements.eu.berlin.#） 和 all_agreements（agreements.#）
    channel.BasicPublish(exchange: "agreements",
                            routingKey: "agreements.eu.berlin",
                            basicProperties: properties,
                            body: body);

               
}