function isValidEmail(data){
	validRegExp = /^[^@]+@[^@]+.[a-z]{2,}$/i;
	strEmail = data;

	// search email text for regular exp matches
	if (strEmail.search(validRegExp) == -1) {
		return false;
	}
	return true;
}

function show_hide(div_id) {
	var obj = document.getElementById(div_id);

	if(obj.style.display == 'block') {
		obj.style.display = 'none';
	} else {
		obj.style.display = 'block';
	}
}

function sendContactForm(f) { // VERSTUUR HET FORMULIER 'f'
	errorsFound = false;  // STANDAARD GEEN FOUTEN GEVONDEN
	if (!isValidEmail(document.getElementById('inp_your_email').value)) { 
		errorsFound = true; 
		alert('Geen geldig e-mailadres gegeven');
		return false; 	
	} else if (!isValidEmail(document.getElementById('inp_their_email').value)) {
		errorsFound = true; 
		alert('Geen geldig e-mailadres gegeven');
		return false; 	
	} else {
		return true;
	}
}

function isValidEmail(str){ 
	var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
	return filterTest(filter,str);
}			

function filterTest(filter,str) {
	if (filter.test(str)) {
		testresults=true;
	} else {
		testresults=false;
	}
	return testresults;		
}