function chlang() {
	var menu = parent.menu.location.href;
	var header = parent.header.location.href;
	var main = parent.main.location.href;
	var endmenu = menu.length;
	var endheader = header.length;
	var endmain = main.length;
	var i;
	var n;
	var found = 0;
	
	for(i = 0; i <= endheader; i++) {
		n = i + 3;
		if (header.substring(i, n) == "chi") {			
			chheader = header.substring(0, i) + "eng" + header.substring(n, endheader);
			chmenu = menu.substring(0, i) + "eng" + menu.substring(n, endmenu);
			chmain = main.substring(0, i) + "eng" + main.substring(n, endmain);

			break;
		}
	}
	
	parent.menu.location.href = chmenu;
	parent.header.location.href = chheader;
	parent.main.location.href = chmain;
}

function chframe(header, main) {
	parent.header.location= header;
	parent.main.location= main;
}

function same(page) {
	if (parent.header){
	if (parent.header.location != page) {
		parent.header.location = page;
	}
	}
	
}

function prevPage() {
	parent.main.history.go(-1);
	parent.header.history.go(-1);
}