function checkform() {
	
	var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
email = document.getElementById('visitormail').value;
valid = emailExp.test(email);

name = document.getElementById('nameis').value;
	if(valid == false && name==""){
	alert('Please enter your name and email.');
	return false;
	} else if (valid==false) {
		alert('Please enter a valid email.');
		return false;
		}else if (valid==true && name==""){
			alert('Please enter your name.');
			return false;
			}
return true;
}