function ExRate(f){
if(f == 0){
document.ex.f.value = 'Euro';
curr1 = 'Euro';
curr2 = 'U.S. Dollar';
document.ex.s.value = 'U.S. Dollar';

del = 1;
}
if(f == 1 || f == 0){
curr1 = document.ex.f.value;
curr2 = document.ex.s.value;
del = 1;
}

if(f == 2){
curr1 = document.ex.f.value;
curr2 = document.ex.s.value;
del = 2;
}

if(f == 3){
curr1 = document.ex.f.value;
curr2 = document.ex.s.value;
del = 1;
}

if(del == 1) {acc = document.ex.fr.value; }
else acc = document.ex.sr.value;

        var req = new Subsys_JsHttpRequest_Js();
        req.onreadystatechange = function() {
            if (req.readyState == 4) {
                if (req.responseJS) {
document.ex.fn.value = req.responseJS.ex;
document.ex.sn.value = req.responseJS.ex1;
if(del == 1) {document.ex.sr.value = req.responseJS.am;document.ex.fr.value = document.ex.fr.value;}
 else  {document.ex.fr.value = req.responseJS.am; document.ex.sr.value = document.ex.sr.value;}
document.getElementById('dat').innerHTML = req.responseJS.dat;

               }
            }
        }
        req.caching = false;
        req.open('POST', 'js/c.php',true);
        req.send({curr1:curr1, curr2:curr2, del:del, acc:acc  });
 }