function validateForm(theform) {
	for (var i=0; i<theform.elements.length; i++) {
		var element = theform.elements[i];
		if (element.className.indexOf("required") !=-1) {
			element.className = "required";
			if (!isFilled(element)) {
				alert("Please enter your " +element.id);
				element.className += " error";
				element.focus();
				return false;
			} 
		}
		if (element.className.indexOf("email") !=-1) {
			element.className = "required";
			if (!isEmail(element)) {
				alert("Please check you have entered a valid email address");
				element.className += " error";
				element.focus();
				return false;
			}
		}
	}
	return true;
}

function isFilled(field) {
	if (field.value.length < 1) {
		return false;
	} else {
		return true;
	}
}
function isEmail(field) {
	if (field.value.indexOf("@") == -1 || field.value.indexOf(".") == -1) {
		return false;
	} else {
		return true;
	}
}