Keyboard

A library for listening to keyboard shortcuts and combos, such as Ctrl + Z, Ctrl + Shift + Z

Install

npm i keyboard-ts

# or
yarn add keyboard-ts

Use

import { Key, Keyboard } from 'keyboard-ts'

const target = document.getElementById('target')
const keyboard = new Keyboard(target)

// listen to Del + Esc
keyboard.on([ Key.Escape, Key.Delete ], () => {
    /* do something ... */
})

// listen to Space
keyboard.on([ Key.Space ], event => {
    // event is classic HTML event
    event.preventDefault()

    /* do something ... */
})

// listen to Ctrl+Z
keyboard.on([[ Key.Ctrl, Key.Z ]], () => {
    /* do something ... */
})

// listen to Ctrl+Shift+Z
keyboard.on([[ Key.Ctrl, Key.Shift, Key.Z ]], () => {
    /* do something ... */
})

// listen to Ctrl+Z or Ctrl+Y
keyboard.on([[ Key.Ctrl, Key.Z ], [ Key.Ctrl, Key.Y ]], () => {
    /* do something ... */
})

// listen to Ctrl+Z+X
keyboard.on([[ Key.Ctrl, Key.Z, Key.X ]], () => {
    /* do something ... */
})

// remove all listeners
keyboard.clear()

API doc

new Keyboard(target: HTMLElement)

Instantiate new keyboard shortcut manager. This manager will listen to key combos pressed on the target HTML element.

keyboard.on(combo: Key[], (event: KeyboardEvent) => void)
keyboard.on(combos: Key[][], (event: KeyboardEvent) => void)

Start listening to when a combo (combination of keyboard keys) is pressed at the same time.

The callback receives the keyboard event triggered by the last pressed key of the combo. (e.g. If Ctrl + Z, triggers Ctrl press event and then Z press event, the callback will receive the Z press event.)

Instead of one combo, and array of combos can be passed in. In that case the callback is triggered if any of the combos is pressed.

keyboard.pause()

Temporarily pause listening to any keyboard combos. Can be reversed by calling keyboard.unpause().

keyboard.unpause()

Start listening again to keyboard combos again after keyboard.pause() was called.

keyboard.clear()

Remove all listeners.

Limitations

1. It is not possible to use window.alert() inside the callback.

import { Key, Keyboard } from 'keyboard-ts'

const target = document.getElementById('target')
const keyboard = new Keyboard(target)

// Do NOT use alert() as a callback!
keyboard.on([ Key.Ctrl, Key.A ], () => {
    ❌ alert('stuff')

    // alert() erases the subsequent 'mouseup' event and this breaks the functionality
    // of the Keyboard class, because it has no way of knowing whether a key was released or not.
})

2. Windows key and select key are not supported

Changelog

• v2.0.0
  • Removed support for Windows key and select key
  • Added support for Macbook CMD key
• v1.2.5
  • Added Limitations to readme
• v1.2.4
  • Fix combos during pause. User can now press part of the combo before or during pause, and the rest after pause.
  • Fix no longer triggering combos when some extra keys are pressed, now combos get triggered only when exactly the combo keys are pressed and nothing else. (e.g. Ctrl + Z combo does not get triggered anymore when user presses Ctrl + Shift + Z)
  • Fixed listening to single combos keyboard.on([ Key.Ctrl, Key.A ], () => {}) where callback was getting triggered when any of the keys from the combo was pressed
• v1.2.3
  • Added methods to listen to keyboard combos