function numbersonly(myfield, e, dec)
{
	var key;
	var keychar;
	
	if (window.event) { key = window.event.keyCode; }
	else if (e) { key = e.which; }
	else { return true; }
	
	keychar = String.fromCharCode(key);

	if ((key==null) || (key==0) || (key==8) || (key==9) || (key==13) || (key==27) ) { return true; }
	else if ((("0123456789").indexOf(keychar) > -1)) { return true; }
	else if (dec && (keychar == ".")) { myfield.form.elements[dec].focus(); return false; }
	else { return false; }
}

function setCost()
{
	document.getElementById('licensecost').innerHTML = 0;
}

function setDVDCost()
{
	document.getElementById('dvdcost').innerHTML = 0;
}

function calculateCost(perstudentfee, perteacherfee, perdvdfee)
{	
	if ((isNaN(document.orderform.Number_of_Students.value)) || (!document.orderform.Number_of_Students.value)) { studentcount = 0; }
	else { studentcount = parseInt(document.orderform.Number_of_Students.value); }
	
	if ((isNaN(document.orderform.Number_of_Teachers.value)) || (!document.orderform.Number_of_Teachers.value)) { teachercount = 0; }
	else { teachercount = parseInt(document.orderform.Number_of_Teachers.value); }
	
	if ((isNaN(document.orderform.DVD1.value)) || (!document.orderform.DVD1.value)) { dvd1count = 0; }
	else { dvd1count = parseInt(document.orderform.DVD1.value); }
	
	if ((isNaN(document.orderform.DVD2.value)) || (!document.orderform.DVD2.value)) { dvd2count = 0; }
	else { dvd2count = parseInt(document.orderform.DVD2.value); }
	
	if ((isNaN(document.orderform.DVD3.value)) || (!document.orderform.DVD3.value)) { dvd3count = 0; }
	else { dvd3count = parseInt(document.orderform.DVD3.value); }
	
	if ((isNaN(document.orderform.DVD4.value)) || (!document.orderform.DVD4.value)) { dvd4count = 0; }
	else { dvd4count = parseInt(document.orderform.DVD4.value); }
	
	if ((isNaN(document.orderform.DVD5.value)) || (!document.orderform.DVD5.value)) { dvd5count = 0; }
	else { dvd5count = parseInt(document.orderform.DVD5.value); }
	
	if ((isNaN(document.orderform.DVD6.value)) || (!document.orderform.DVD6.value)) { dvd6count = 0; }
	else { dvd6count = parseInt(document.orderform.DVD6.value); }
	
	if ((isNaN(document.orderform.DVD7.value)) || (!document.orderform.DVD7.value)) { dvd7count = 0; }
	else { dvd7count = parseInt(document.orderform.DVD7.value); }
	
	if ((isNaN(document.orderform.DVD8.value)) || (!document.orderform.DVD8.value)) { dvd8count = 0; }
	else { dvd8count = parseInt(document.orderform.DVD8.value); }
	
	var dvdcount = dvd1count + dvd2count + dvd3count + dvd4count + dvd5count + dvd6count + dvd7count + dvd8count;
	var studenttotal = studentcount * perstudentfee;
	var teachertotal = teachercount * perteacherfee;
	var dvdtotal = dvdcount * perdvdfee;
	
	var total = studenttotal + teachertotal + dvdtotal;
	
	document.getElementById('licensecost').innerHTML = Math.ceil(total.toFixed(2));
}

function calculateDVDCost(perdvdfee)
{	
	if ((isNaN(document.orderform.DVD1.value)) || (!document.orderform.DVD1.value)) { dvd1count = 0; }
	else { dvd1count = parseInt(document.orderform.DVD1.value); }
	
	if ((isNaN(document.orderform.DVD2.value)) || (!document.orderform.DVD2.value)) { dvd2count = 0; }
	else { dvd2count = parseInt(document.orderform.DVD2.value); }
	
	if ((isNaN(document.orderform.DVD3.value)) || (!document.orderform.DVD3.value)) { dvd3count = 0; }
	else { dvd3count = parseInt(document.orderform.DVD3.value); }
	
	if ((isNaN(document.orderform.DVD4.value)) || (!document.orderform.DVD4.value)) { dvd4count = 0; }
	else { dvd4count = parseInt(document.orderform.DVD4.value); }
	
	if ((isNaN(document.orderform.DVD5.value)) || (!document.orderform.DVD5.value)) { dvd5count = 0; }
	else { dvd5count = parseInt(document.orderform.DVD5.value); }
	
	if ((isNaN(document.orderform.DVD6.value)) || (!document.orderform.DVD6.value)) { dvd6count = 0; }
	else { dvd6count = parseInt(document.orderform.DVD6.value); }
	
	if ((isNaN(document.orderform.DVD7.value)) || (!document.orderform.DVD7.value)) { dvd7count = 0; }
	else { dvd7count = parseInt(document.orderform.DVD7.value); }
	
	if ((isNaN(document.orderform.DVD8.value)) || (!document.orderform.DVD8.value)) { dvd8count = 0; }
	else { dvd8count = parseInt(document.orderform.DVD8.value); }
	
	var dvdcount = dvd1count + dvd2count + dvd3count + dvd4count + dvd5count + dvd6count + dvd7count + dvd8count;
	var total = dvdcount * perdvdfee;
	
	document.getElementById('dvdcost').innerHTML = Math.ceil(total.toFixed(2));
}