function cent(amount) {
// returns the amount in the .99 format
	return (amount == Math.floor(amount)) ? amount + '.00' : (  (amount*12.5 == Math.floor(amount*12.50)) ? amount + '0' : amount);
}

function update(form) {
	aantal = (form.aantal1.value - 0);
	var totaal = (aantal - 0) * (form.cost.value - 0) + (form.administrationCost.value - 0);
	form.totaal.value = '€' + cent(totaal);

}

function emailCheck (emailStr) {
var checkTLD=1;
var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
var emailPat=/^(.+)@(.+)$/;
var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
var validChars="\[^\\s" + specialChars + "\]";
var quotedUser="(\"[^\"]*\")";
var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
var atom=validChars + '+';
var word="(" + atom + "|" + quotedUser + ")";
var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
var matchArray=emailStr.match(emailPat);

if (matchArray==null) {

alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
}
var user=matchArray[1];
var domain=matchArray[2];

// Start by checking that only basic ASCII characters are in the strings (0-127).

for (i=0; i<user.length; i++) {
if (user.charCodeAt(i)>127) {
alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
   }
}
for (i=0; i<domain.length; i++) {
if (domain.charCodeAt(i)>127) {
alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
   }
}

if (user.match(userPat)==null) {

alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
}

var IPArray=domain.match(ipDomainPat);
if (IPArray!=null) {


for (var i=1;i<=4;i++) {
if (IPArray[i]>255) {
alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
   }
}
return true;
}

var atomPat=new RegExp("^" + atom + "$");
var domArr=domain.split(".");
var len=domArr.length;
for (i=0;i<len;i++) {
if (domArr[i].search(atomPat)==-1) {
alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
   }
}

if (checkTLD && domArr[domArr.length-1].length!=2 && 
domArr[domArr.length-1].search(knownDomsPat)==-1) {
alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
}

if (len<2) {
alert("Het e-mailadres dat je invulde is ongeldig!");
return false;
}

return true;
}

//  End -->