Implement new managed client.

Source/MQTTnet.Extensions.ManagedClient/New/Events/SubscribeProcessedEventArgs.cs

@@ -0,0 +1,27 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using MQTTnet.Client;
+using MQTTnet.Packets;
+
+namespace MQTTnet.Extensions.ManagedClient
+{
+    public sealed class SubscribeProcessedEventArgs : EventArgs
+    {
+        public SubscribeProcessedEventArgs(MqttClientSubscribeOptions options, MqttClientSubscribeResultCode result, IReadOnlyCollection<MqttUserProperty> userProperties)
+        {
+            Options = options ?? throw new ArgumentNullException(nameof(options));
+            Result = result;
+            UserProperties = userProperties;
+        }
+
+        public MqttClientSubscribeOptions Options { get; }
+
+        public MqttClientSubscribeResultCode Result { get; }
+
+        public IReadOnlyCollection<MqttUserProperty> UserProperties { get; }
+    }
+}