// JavaScript Document 2009
// Radio Button Validation
// copyright Stephen Chapman, 15th Nov 2004,14th Sep 2005
// you may copy this function but please keep the copyright notice with it
function valButton(btn) {
    var cnt = -1;
    for (var i=btn.length-1; i > -1; i--) {
        if (btn[i].checked) {cnt = i; i = -1;}
    }
    if (cnt > -1) return btn[cnt].value;
    else return null;
}
                  

function validateNB(frm)
	{
	
	if(frm.naam.value == "") 
		{
        alert("Graag je naam invullen!");
        frm.naam.focus();
        return false;
		}
	
		
	if(frm.email.value == "") 
		{
        alert("Graag je emailadresadres invullen");
        frm.email.focus();
        return false;
		}
	if(isEmail(frm.email.value) == false && frm.email.value != "") 
		{
        alert("Check de notatie van je emailadres!");

        frm.email.focus();
        return false;
		}
		
	
	
		
	if(frm.nieuwsbrief)
		{
		if(frm.nieuwsbrief.value == "koe") 
			{
			alert("Wilt u de nieuwsbrief ontvangen of niet meer ontvangen?");
			
			return false;
			}
		}
		

		
		
		
		
	return true;
	}
	
function isEmail(string) 
	{
    if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
        return true;
    else
        return false;
}