var submitted=0;

function checkContactForm() {
	if (document.contactForm.fullname.value=='') {
		alert( "Vul uw naam in");
	} else if (!isEmail(document.contactForm.email.value)) {
		alert( "Vul een geldig e-mailadres in");
	} else if (!submitted) {
		submitted=1;
		document.contactForm.submit();
	}
}

function isEmail(str) {
	return (str.match(new RegExp('^[\'_a-zA-Z0-9-]+(\.[\'_a-zA-Z0-9-]+)*@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*\.(([a-zA-Z]{2,3})|(aero|coop|info|museum|name))$')))?true:false;	
}

function toggleSearch() {
	if (document.searchForm.search.value != '') {
		document.getElementById( "searchButton").style.visibility = "visible";
	} else {
		document.getElementById( "searchButton").style.visibility = "hidden";
	}
}