var ns4;
var ie4;
var ie5;
var ns6;
var xLoaded=false;

function getElem(id) {
var elem = null;
  if(ns4){
	elem=document.layers[id];
  }
  else if(ie4){
	elem=document.all[id];
  }
  else if(ie5 || ns6){
	elem=document.getElementById(id);
  }
  return elem;
}

function xSet(a,data) {
  xInit();
  var id;
  if (a==1) id="c_a";
  if (a==2) id="c_r";  
  elem=getElem(id);
  if (elem!=null) elem.value=data;
}

function xInit() {
  if (xLoaded==false) {
    ns4 = (document.layers);
    ie4 = (document.all && !document.getElementById);
    ie5 = (document.all && document.getElementById);
    ns6 = (!document.all && document.getElementById);
	xLoaded=true;
	  
    xSet(1,"I");
    xSet(2,"I");
  }	
}

function xGet(a) {
  var id;
  var ret=null;
  if (a==1) id="c_a";
  if (a==2) id="c_r";  
  elem=getElem(id);
  if (elem!=null) ret=elem.value;
  return ret;
}


function jump(url) {
  document.location.href=url;
}
  
function xJump(url) {
  dat_a=xGet(1);
  dat_r=xGet(2);
  jump(url+"?a="+dat_a+"&r="+dat_r);
  return false;
}
<!--
//<a href="#" onclick="xJump('http:\\www.index.hu');">Click</a>

//alap ertek: A
//ez toltodik le

//init ertek: I
//ez inicializalodik

//load ertek: L
//onload  xSet(1,'l')

//error ertek: E
//onerror  xSet(1,'e')
 -->