当用户向我的机器人发送消息时，他会收到欢迎消息。但是当用户响应时，机器人会再次发送欢迎消息。我怎样才能解决这个问题？

我正在使用 Microsoft Bot Framework 开发聊天机器人，最近将框架 3.0 升级到 3.5。升级之前它工作正常，但现在

当用户向我的机器人发送消息时，他会收到欢迎消息。但是当用户响应时，机器人会再次发送欢迎消息。 我怎样才能解决这个问题？这是代码。

private Activity HandleSystemMessage(Activity message)
        {
            if (message.Type == ActivityTypes.DeleteUserData)
            {
                // Implement user deletion here
                // If we handle user deletion, return a real message
            }
            else if (message.Type == ActivityTypes.ContactRelationUpdate)
            {
                // Handle conversation state changes, like members being added and removed
                // Use Activity.MembersAdded and Activity.MembersRemoved and Activity.Action for info
                // Not available in all channels               
            }
            else if (message.Type == ActivityTypes.ConversationUpdate)
            {
                // Handle conversation state changes, like members being added and removed
                // Use Activity.MembersAdded and Activity.MembersRemoved and Activity.Action for info
                // Not available in all channels
                logger.Debug("Activity Type " + message.Type);
                logger.Debug("Inside conversation update and activity Id is :-"+ message.Id);
                ConnectorClient connector = new ConnectorClient(new System.Uri(message.ServiceUrl));
                Activity reply = message.CreateReply(ConstantsTable.WelcomeMessage);                                
                connector.Conversations.ReplyToActivityAsync(reply);
                message.Type = ActivityTypes.Message;                    
            }
            else if (message.Type == ActivityTypes.ContactRelationUpdate)
            {
                // Handle add/remove from contact lists
                // Activity.From + Activity.Action represent what happened
            }
            else if (message.Type == ActivityTypes.Typing)
            {
                // Handle knowing tha the user is typing
                ConnectorClient connector = new ConnectorClient(new System.Uri(message.ServiceUrl));
                Activity reply = message.CreateReply("You are typing");
                connector.Conversations.ReplyToActivityAsync(reply);
            }
            else if (message.Type == ActivityTypes.Ping)
            {
                ConnectorClient connector = new ConnectorClient(new Uri(message.ServiceUrl));
                Activity reply = message.CreateReply("Hello PING. Please reply");
                connector.Conversations.ReplyToActivityAsync(reply);
            }

            return message;
        }

但在本地模拟器中，当仅发布这种情况时，它工作正常。 请帮忙。

我相信这可能与几天前推出的一项更改有关； Direct Line 将发送更多信息ConversationUpdate消息比以前多。

检查公告 https://github.com/Microsoft/BotBuilder/issues/2065 and a 相关问题 https://github.com/Microsoft/BotBuilder/issues/2093（与你的类似，但是在node.js).

首先ConversationUpdate当机器人添加到对话中时发送。 之后，每增加一个ConversationUpdate当新用户加入对话时发送。

所以，我认为这里的解决方案是检查添加的成员（activity.MembersAdded)

    else if (message.Type == ActivityTypes.ConversationUpdate)
    {
        if (message.MembersAdded.Any(o => o.Id == message.Recipient.Id))
        {
            // logic
        }
    }