Javascript/jQuery Keypress logging

Question

I would like to be able to log the key presses on a specific page, trying to implement an \'Easter egg\' type functionality where when the correct keys are pressed in the co

Answer 1

In such circumstances it might also be useful to be able to check for the ctl/alt/shift keys:

if (e.altKey) {
}

if (e.ctrlKey) {
}

if (e.shiftKey) {
}

For keypress codes, the following object literal should help:

var Key =
{
    BACKSPACE: 8,
    TAB: 9,
    ENTER: 13,
    ESC: 27,
    PAGEUP: 33,
    PAGEDOWN: 34,
    END: 35,
    HOME: 36,
    LEFT: 37,
    UP: 38,
    RIGHT: 39,
    DOWN: 40,
    HELP: 47,
    H: 72,
    K: 75,
    N: 78,
    R: 82,
    NUMERIC_PLUS: 107,
    F1: 112,
    F2: 113,
    F3: 114,
    F4: 115,
    F5: 116,
    F6: 117,
    F7: 118,
    F8: 119,
    F9: 120,
    F10: 121,
    F11: 122,
    F12: 123,
    PLUS: 187,
    MINUS: 189,
    V: 86
}

So instead of:

  switch(event.keyCode) { 
    case 40: 
      keypresses.push('down'); 
    break; 
    case 38: 
      keypresses.push('up'); 
  } 

We can say:

switch(event.keyCode) { 
    case Key.DOWN: 
        keypresses.push('down'); 
        break; 
    case Key.UP: 
        keypresses.push('up'); 
        break; 
} 

This promotes self documenting code, and is more readable and maintainable.