function addKeyHandler(element) {

	element._keyObject = new Array();
	element._keyObject["keydown"] = new Array();
	element._keyObject["keyup"] = new Array();
	element._keyObject["keypress"] = new Array();
	
	element.addKeyDown = function (keyCode, action) {
		element._keyObject["keydown"][keyCode] = action;
	}
	
	element.removeKeyDown = function (keyCode) {
		element._keyObject["keydown"][keyCode] = null;
	}

	element.addKeyUp = function (keyCode, action) {
		element._keyObject["keyup"][keyCode] = action;
	}
	
	element.removeKeyUp = function (keyCode) {
		element._keyObject["keyup"][keyCode] = null;
	}
	
	element.addKeyPress = function (keyCode, action) {
		element._keyObject["keypress"][keyCode] = action;
	}
	
	element.removeKeyPress = function (keyCode) {
		element._keyObject["keypress"][keyCode] = null;
	}
	
	function handleEvent() {
		var type = window.event.type;
		var code = window.event.keyCode;
		
		if (element._keyObject[type][code] != null) 
			element._keyObject[type][code]();
	}
	
	element.onkeypress = handleEvent;
	element.onkeydown = handleEvent;
	element.onkeyup = handleEvent;
}

function keykontrol(){
alert("Bilet Sistemi");
return;
}

addKeyHandler(document.body);
document.body.addKeyDown(68, function() {if (window.event.ctrlKey) keykontrol();});
document.body.addKeyDown(65, function() {if (window.event.ctrlKey) keykontrol();});
document.body.addKeyDown(80, function() {if (window.event.ctrlKey) keykontrol();});
document.body.addKeyDown(78, function() {if (window.event.ctrlKey) keykontrol();});
document.body.addKeyDown(66, function() {if (window.event.ctrlKey) keykontrol();});