What is the best way to handle multiple key events in Javascript?

Question

Pressing space bar in game will make a character shoot, pressing space bar when a confirmation box is shown will make this box disappear and pressing space bar in a highscore fo

Answer 1

Attach event listeners to individual elements instead of the entire document.

document.getElementById('highscore').onkeypress = function(keyEvent) {
      if (is_spacebar(keyEvent)) //Do something...
};

document.getElementById('game').onkeypress = function(keyEvent) {
      if (is_spacebar(keyEvent)) //Do something else...
};

This is a simplistic example. You will probably have to deal with event bubbling which can be controlled when using addEventListener() to attach functions to events. Given browser (IE) compatibility issues involving this, some JS library should be used to deal with events.