function isEmpty(value){
	return(value.length==0 || value==null);
}



//validateContactForm()
function validateOrderForm(form,language){
	var result = false;
	var errorString="";	
	var firstName = form.firstName.value;
	var lastName = form.lastName.value;
	var phone = form.phone.value;
	var visit = form.visit.value;
	var order = form.order.value;
	
	if(isEmpty(firstName)){
		errorString +=(language=="cs")?"\nVyplňte Vaše jméno...":"\nPlease, fill in your first name...";
	}
	if(isEmpty(lastName)){
		errorString +=(language=="cs")?"\nVyplňte Vaše příjmení...":"\nPlease, fill in your last name...";
	}
	if(isEmpty(phone)){
		errorString +=(language=="cs")?"\nVyplňte Váš telefon...":"\nPlease, fill in your  phone...";
	}
	if(isEmpty(visit)){
		errorString +=(language=="cs")?"\nVyplňte preferovaný termín návštěvy...":"\nPlease, fill in the preferred date and time of your visit...";
	}
	if(isEmpty(order)){
		errorString +=(language=="cs")?"\nVyplňte specifikaci požadovaného materiálu...":"\nPlease, fill in the specification of the  material required...";
	}
		
	if(errorString.length){
		alert(errorString);
	}else{
		result=true;
	}
	return result;
}