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Receive a Message/

Receive a Message

Feature Description

To receive messages, you need to listen for the MESSAGE_RECEIVED event.

Listening for an Event

Note:
Call this API to listen for events before calling the login API in order to avoid missing the events delivered by the SDK.
API
chat.on(eventName, handler, context);
Parameter
Name
Type
Description
eventName
String
Event name. All event names are stored in the TencentCloudChat.EVENT variable. To view all the events, use console.log(TencentCloudChat.EVENT).
handler
Function
Event handling method. When an event is triggered, this handler will be called to handle it.
context
* | undefined
The context expected for handler execution
Sample
let onMessageReceived = function(event) {
  // event.data - An array that stores `Message` objects - [Message]
  // For details of Message, please refer to https://www.tencentcloud.com/document/product/1047/47990
  const messageList = event.data;
  messageList.forEach((message) => {
    if (message.type === TencentCloudChat.TYPES.MSG_TEXT) {
      // Text message
    } else if (message.type === TencentCloudChat.TYPES.MSG_IMAGE) {
      // Image message
    } else if (message.type === TencentCloudChat.TYPES.MSG_AUDIO) {
      // Audio message
    } else if (message.type === TencentCloudChat.TYPES.MSG_VIDEO) {
      // Video message
    } else if (message.type === TencentCloudChat.TYPES.MSG_FILE) {
      // File message
    } else if (message.type === TencentCloudChat.TYPES.MSG_CUSTOM) {
      // Custom message
    } else if (message.type === TencentCloudChat.TYPES.MSG_MERGER) {
      // Merged message
    } else if (message.type === TencentCloudChat.TYPES.MSG_LOCATION) {
      // Geographical location message
    } else if (message.type === TencentCloudChat.TYPES.MSG_GRP_TIP) {
      // Group tip message
    } else if (message.type === TencentCloudChat.TYPES.MSG_GRP_SYS_NOTICE) {
      // Group system notification
    }
  });
};
chat.on(TencentCloudChat.EVENT.MESSAGE_RECEIVED, onMessageReceived);

Canceling Event Listening

API
chat.off(eventName, handler, context);
Parameter

Name
Type
Description
eventName
String
Event name. All event names are stored in the TencentCloudChat.EVENT variable. To view all the events, use console.log(TencentCloudChat.EVENT).
handler
Function
Event handling method. When an event is triggered, this handler will be called to handle it.
context
* | undefined
The context expected for handler execution
Sample
let onMessageReceived = function(event) {
  // event.name - TencentCloudChat.EVENT.MESSAGE_RECEIVED
  // event.data - An array that stores `Message` objects - [Message]
};
chat.off(TencentCloudChat.EVENT.MESSAGE_RECEIVED, onMessageReceived);