Callbacks

WebSerial comes with a single callback called onMessage. It’s responsible for notifying your firmware whenever it has received a command/message from user via webserial terminal.

If the callback is not registered, then the command received from terminal is simply discarded.

onMessage Callback

The onMessage callback is triggered whenever a command/message is received from the user via the webserial terminal. It’s a convenient way to handle incoming messages and execute specific actions based on the content of the message.

Handle Incoming Messages as String

// If you want to handle incoming messages as strings
WebSerial.onMessage([](const String& msg) {
  Serial.println(msg);
});

Handle Incoming Messages as Data Streams

// If you want to handle incoming messages as data streams
WebSerial.onMessage([&](uint8_t *data, size_t len) {
  Serial.printf("Received %lu bytes from WebSerial: ", len);
  Serial.write(data, len);
  Serial.println();
  WebSerial.println("Received Data...");
  String d = "";
  for(size_t i=0; i < len; i++){
    d += char(data[i]);
  }
  WebSerial.println(d);
});