//////////////////[ Key down event handler ]/////////////////////
//Event handler class to attach events
var EventUtil = {
addHandler: function(element, type, handler){
if (element.addEventListener){
element.addEventListener(type, handler, False);
} else if (element.attachEvent){
element.attachEvent("on" + type, handler);
} else {
element["on" + type] = handler;
}
}
};

// Attach Key down/up events to document
EventUtil.addHandler(document, "keydown", function(event){keyDownHandler(event)});
EventUtil.addHandler(document, "keyup", function(event){keyUpHandler(event)});

//Checks for shift and Ctrl key press
function keyDownHandler(e)
{
if (!e) var e = window.event;
var target = (!e.target) ? e.srcElement : e.target;
if (e.keyCode == 16 && !global.shiftKey) { //Shift Key
global.shiftKey = True;
}
if (e.keyCode == 17 && !global.ctrlKey) { //Ctrl Key
global.ctrlKey = True;
}
}
//Checks for shift and Ctrl key release
function keyUpHandler(e){
if (!e) var e = window.event;
if (e.keyCode == 16 && global.shiftKey) { //Shift Key
global.shiftKey = False;
}
if (e.keyCode == 17 && global.ctrlKey) { //Ctrl Key
global.ctrlKey = False;
}
}