var ImgList;
var action = "false";
var i = './img/';

function preLoad() {
	ImgList = new Array
("bk_2.gif"
,"room1_2.gif"
,"nt_2.gif"
);
	onImages = new Array();
	for ( field in ImgList ) {
		onImages[field] = new Image();
		onImages[field].src = i+ ImgList[field];
	}
	action = "true";
}

function ChgImg(btn,img){
	document.images[btn].src=i + img;
}