Solution for unable to create "dead-letter-exchange" in RabbitMQ

在參考 Dead-Letter-Exchange 進行Dead-letter-exchange的理解，

在本地時，想要創建 Dead-letter-exchange 時，一直報錯，錯誤如下：

Unhandled Exception: RabbitMQ.Client.Exceptions.OperationInterruptedException: The AMQP operation was interrupted: AMQP close-reason, initiated by Peer, code=406, text="PRECONDITION_FAILED - inequivalent arg 'x-dead-letter-exchange' for queue 'q_test' in vhost '/': received the value 'q-dead-letter-exchange' of type 'longstr' but current is none", classId=50, methodId=10, cause=
   at RabbitMQ.Client.Impl.SimpleBlockingRpcContinuation.GetReply(TimeSpan timeout)
   at RabbitMQ.Client.Impl.ModelBase.QueueDeclare(String queue, Boolean passive, Boolean durable, Boolean exclusive, Boolean autoDelete, IDictionary`2 arguments)
   at RabbitMQ.Client.Impl.AutorecoveringModel.QueueDeclare(String queue, Boolean durable, Boolean exclusive, Boolean autoDelete, IDictionary`2 arguments)
   at CNBlogs.Question.EventBusRabbitMQ.EventBusRabbitMQ.CreateConsumerChannel()

去官網查了查，姿勢也正確，先聲明一個Exchange

channel.ExchangeDeclare("q-dead-letter-exchange", type: "direct");

然后再指定 x-dead-letter-exchange 參數

var args = new Dictionary<string, object>()
            {
                {"x-dead-letter-exchange", "q-dead-letter-exchange"}
            };

最后放到隊列聲明里面：

 channel.QueueDeclare(queue: _queueName,
                                 durable: true,
                                 exclusive: false,
                                 autoDelete: false,
                                 arguments: args);

然而，每次一運行就報上面那個錯誤，最后子啊Github上找到了答案

• using a dead letter exchange

原因可能是我原來的隊列中，因為有尚未確認的消息在。然后，把RabbitMQ 中的Queue 和Exchange 刪除，重新運行程序就成功了。下面是Queue和Exchange 的截圖