The midimessage event of the Web MIDI API is fired when the MIDI port corresponding to this MIDIInput finishes receiving one or more MIDI messages. An instance of MIDIMessageEvent containing the message that was received is passed to the event handler.

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("midimessage", (event) => {});

onmidimessage = (event) => {};

An MIDIMessageEvent. Inherits from Event.

This interface also inherits properties from Event.

MIDIMessageEvent.data

A Uint8Array containing the data bytes of a single MIDI message. See the MIDI specification for more information on its form.

In the following example midimessage events are listened for on all input ports. When a message is received the MIDIMessageEvent.data property is printed to the console.

inputs.forEach((input) => {
  input.onmidimessage = (message) => {
    console.log(message.data);
  };
});