function formValidator(){
var firstname = document.getElementById('first_name');
var lastname = document.getElementById('last_name');
var number = document.getElementById('number');
var email = document.getElementById('email');

if(isAlphabet(firstname, "Please enter only letters for your name")){
	if(isAlphabet(lastname, "Please enter only letters for your last name")){
		if(isNumeric(number, "Please enter a valid phone number")){
			if(emailValidator(email, "Please enter a valid email address")){
				return true;	
			}

	
		}
	}
}
return false;

}



function isEmpty(elem, helperMsg){
	if(elem.value.length == 0){
		alert(helperMsg);
		elem.focus(); // set the focus to this input
		return true;
	}
	return false;
}




function isAlphabet(elem, helperMsg){
	var alphaExp = /^[a-zA-Z]+$/;
	if(elem.value.match(alphaExp)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}


function isNumeric(elem, helperMsg){
	var numericExpression = /^[0-9]+$/;
	if(elem.value.match(numericExpression)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}


function emailValidator(elem, helperMsg){
	var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
	if(elem.value.match(emailExp)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}







// JavaScript Document