// JavaScript Document

function show(inputData) {
var buttonID=document.getElementById( "button_" + inputData );
var count = 1;

do {
var objID=document.getElementById( "button_" + count );
objID.src="img/btn0" + count + ".jpg";
}while(count++ < 2);
var objID=document.getElementById( "button_" + inputData );
objID.src="img/btn0" + inputData + "_on.jpg";

count = 1;

do {
var objID=document.getElementById( "layer_" + count );
objID.style.display='none';
}while(count++ < 2);

var objID=document.getElementById( "layer_" + inputData );

objID.style.display='block';
<!-- objID.className='open'; -->
<!-- buttonID.src='img/btn01.jpg'; -->
}