Question

how do i check if a combination of keys are pressed with jquery?

lets say i want to fire up an alert only when the up and down arrow keys are pressed at the same time.

right now im just using:

switch (event.which) {
    case 40:
        alert('down');
        break;
    case 38:
        alert('up');
        break;
    case 37:
        alert('left');
        break;
    case 39:
        alert('right');
        break;
}

Answer 1

Set flags. When one key goes down, if it’s a certain keyCode, set your flag myKeyIsDown = true. When it comes up, set the flag back to false. When your second key goes down, if it is of a certain keyCode and your myKeyIsDown flag is true, you’ve got two keys down.