Receive messages

Receive real-time messages through the Chat SDK's message listener.

Register a message listener

Use NCEngine.addMessageHandler to register a handler that receives all incoming messages. Register the listener before calling connect.

TypeScript

import { NCEngine, MessageHandler } from '@nexconn/chat';

NCEngine.addMessageHandler('my-handler', new MessageHandler({
  onMessageReceived({ messages }) {
    messages.forEach((msg) => {
      console.log('Received:', msg.messageType, msg.content);
    });
  },
}));

Message object properties

Each received message contains the following properties:

Property	Type	Description
messageId	string	Unique message ID assigned by the server
messageType	string	Message type identifier (e.g., RC:TxtMsg)
content	T	Message content (varies by message type)
senderUserId	string	Sender's user ID
channelId	string	Channel ID
channelType	ChannelType	Channel type
sentTime	number	Server timestamp

Handle different message types

TypeScript

import { NCEngine, MessageHandler, MessageType, TextMessageContent, ImageMessageContent } from '@nexconn/chat';

NCEngine.addMessageHandler('type-handler', new MessageHandler({
  onMessageReceived({ messages }) {
    messages.forEach((msg) => {
      switch (msg.messageType) {
        case MessageType.TEXT: {
          const content = msg.content as TextMessageContent;
          console.log('Text:', content.text);
          break;
        }
        case MessageType.IMAGE: {
          const content = msg.content as ImageMessageContent;
          console.log('Image URL:', content.remoteUrl);
          break;
        }
        default:
          console.log('Other message type:', msg.messageType);
      }
    });
  },
}));

Remove a message listener

TypeScript

NCEngine.removeMessageHandler('my-handler');

tip

• You can register multiple message handlers with different uniqueId values.
• Messages from all channel types (direct, group, open channel, community) are delivered through the same listener. Use channelType to filter.