I am having problems with 3+ keys pressed

Question

My JS mini-game don't work correctly. It only records the first two key pressed.

You can see the problem in this jsFiddle

My code is really big, I am not sure what to put here, but I think the problem is here:

document.onkeypress=function(e){
    var charCode;

    e=e||window.event;

    charCode=typeof e.which=="number"?e.which:e.keyCode;

    if((charCode>=102&&charCode<=104)||charCode==106){
        getKey(charCode==106?4:charCode-101);//F-G-H-J=1-2-3-4
    }
    return false;
};

Answer 1

Most keyboards have limits on how many simultaneous keys they can handle. Keys like shift and ctrl can often be handled on top of whatever that simultaneous limit is.

Answer 2

Try using onkeydown to track when a key is pressed, and onkeyup when a key is released. You might track which ones are currently pressed in an array or something.

EDIT: Nevermind. Your game worked fine for me with up to four keypresses. Your commenter was on to something; I think your keyboard just can't handle it.