Compatible with queues that have been created. #772

src/DotNetCore.CAP.RabbitMQ/CAP.RabbiMQOptions.cs

@@ -82,9 +82,9 @@ namespace DotNetCore.CAP
         public class QueueArgumentsOptions
         {
             /// <summary>
-            /// Gets or sets queue mode by supplying the 'x-queue-mode' declaration argument with a string specifying the desired mode. Default 'default'
+            /// Gets or sets queue mode by supplying the 'x-queue-mode' declaration argument with a string specifying the desired mode.
             /// </summary>
-            public string QueueMode { get; set; } = "default";
+            public string QueueMode { get; set; }
 
             /// <summary>
             /// Gets or sets queue message automatic deletion time (in milliseconds) "x-message-ttl", Default 864000000 ms (10 days).

src/DotNetCore.CAP.RabbitMQ/RabbitMQConsumerClient.cs

@@ -116,9 +116,14 @@ namespace DotNetCore.CAP.RabbitMQ
 
                     var arguments = new Dictionary<string, object>
                     {
-                        {"x-queue-mode", _rabbitMQOptions.QueueArguments.QueueMode},
                         {"x-message-ttl", _rabbitMQOptions.QueueArguments.MessageTTL}
                     };
+
+                    if (!string.IsNullOrEmpty(_rabbitMQOptions.QueueArguments.QueueMode))
+                    {
+                        arguments.Add("x-queue-mode", _rabbitMQOptions.QueueArguments.QueueMode);
+                    }
+
                     _channel.QueueDeclare(_queueName, durable: true, exclusive: false, autoDelete: false, arguments: arguments);
                 }
             }