IE = false; NN = false;
if(navigator.appName.toLowerCase().indexOf('netscape') != -1){NN=true;} 
else if(navigator.appName.toLowerCase().indexOf('internet explorer') != -1){IE=true;}
var venster = '';
function openWindow(url, name, w, h, menubar, scroll){
	if(document.getElementById) {
		centerX = parseInt(screen.width / 2);
		centerY = parseInt(screen.height / 2);
	} else {
		centerX = parseInt(screen.availWidth / 2);
		centerY = parseInt(screen.availHeight / 2);
	}
	windowLeft = centerX - parseInt(w/2);
	windowTop = centerY - parseInt(h/2);
	parameters  = 'toolbar=0,location=0,resize=1,menubar=' + menubar;
	parameters += ',width=' + w + ',height=' + h + ',top=' + windowTop + ',left=' + windowLeft;
	if(scroll != null) parameters += ',scrollbars=1';
	venster = window.open(url, name, parameters);
	if(!venster.opener) venster.opener = self;
	if(window.focus){venster.focus()}
}

function validateContact(id) { 
	var val, formId, nm, errors='';
	var regExpEmail = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if(document.getElementById){formId = document.getElementById(id);}
	else{formId = document.forms[id];}
	for(i=0 ; i < formId.elements.length; i++){
		if(formId.elements[i].type != "hidden"){
			val = formId.elements[i].value ;
			nm = formId.elements[i].name ;
			if (val.length == 0) {
			    if (nm == "naam" || nm == "telefoon" || nm == "email") {
			        errors += "\n -in " + nm + " een ";
                    if(nm == "email"){errors += "e-mailadres";}
                    else if(nm == "telefoon"){errors += "telefoonnummer";}
                    else {errors += nm;}
                 }
			} else if (nm == "email" && !regExpEmail.test(val)){errors += "\n -in " + nm + " een geldig e-mailadres";}
		}}	
	if(errors != ""){			
		alert('De volgende informatie ontbreekt:\n\n'+ errors +'\t\t\n\n');
		return false;
	}else{return true;}
}

function validateVragen(id) { 
	var formId, nm, errors='';
	if (document.getElementById) {formId = document.getElementById(id);}
	else {formId = document.forms[id];}
	for(i=0; i < formId.elements.length; i++){
		if(formId.elements[i].type != "hidden"){
			val = formId.elements[i].value ;
			nm = formId.elements[i].name ;
			if (nm.indexOf('vraag') != -1) {                    
               if (!formId.elements[i].checked && !formId.elements[i+1].checked ) errors += nm + '\n';
               i++;
            }
		}}
	if (errors != ''){			
		alert( "U heeft nog geen antwoord gegeven op:\n" + errors +"\n");
		return false;
	} else { return true;}
}

function submitLogon(id) { 
	var val, formId, formNext, nm, errors='';
	if(document.getElementById){formId = document.getElementById(id);}
	else{formId = document.forms[id];}
	for (i=0 ; i < formId.elements.length; i++) {
		if (formId.elements[i].type != "submit" && formId.elements[i].type != "hidden"){
			val = formId.elements[i].value ;
			nm = formId.elements[i].name ;
			if(val.length == 0){errors += "\n -in " + nm + " een " + nm ;}
			else{ 
				if(nm == 'gebruikersnaam'){
					formId.loginnaam.value = val;
					formId.gebruikersnaam.value = '';
				}
				if(nm == 'wachtwoord'){
					formId.loginpasswd.value = hex_md5(val);
					formId.wachtwoord.value = '';
				}}}}	
	if (errors != ""){			
		alert('De volgende informatie ontbreekt:\n\n'+ errors +'\n\n');
		return false;
	} else { return true;}
}