<!--------------------------------------- Checken des BrowserTyps und BrowserVersion -->
var browser = new String("");
if(navigator.appName == "Netscape"){
  if(parseInt(navigator.appVersion) < 5){
    browser = "ns4"; }
  else{
    browser = "ns6"; }
}
else{
  var s = new String("");
  s = navigator.userAgent;
  if(s.indexOf("MSIE 5")){
    browser = "ie5"; }
  else{
    browser = "ie4"; }
}
<!-- jetzt ist 'browser' mit BrowserTyp und BrowserVersion belegt -->

<!----------------------------------------- Funktionen zum Anzeigen eines Objektes (Grafikmenüs) -->
function get_element(name)
{
  if(browser == "ie5" || browser == "ns6")
  {
    return window.document.getElementById(name);
  }
  else if(browser == "ns4")
  {
    return eval("window.document.layers." + name);
  }
  else if(browser == "ie4")
  {
    return eval("window.document.all." + name);
  }
}

function show_object(x)
{
  if(browser == "ns4"){
    get_element(x).visibility="show"; }
  else{
    get_element(x).style.visibility="visible"; }
}

function hide_object(x)
{
  if(browser == "ns4"){
    get_element(x).visibility="hide"; }
  else{
    get_element(x).style.visibility="hidden"; }
}