function validateContactOnSubmit(theForm) {
		  var reason = "";
		  reason += validateEmpty(theForm.naam ,  "Uw naam" ,"", "#ffffff");
		  reason += validateEmail(theForm.email , "#ffffff");
		  reason += validateEmpty(theForm.opmerking ,  "Uw bericht" ,"", "#ffffff");
	
		  
		  if (reason != "") {
		   alert("Sommige verplichte velden zijn niet ingevuld \n\n" + reason);
		    return false;
		  }
		
		  return true;
		}
		

		
		
		function validateEmpty(fld, fieldname,standard, color) {
		    var error = "";
		 
		    if (fld.value.length == 0 ) {
		        fld.style.backgroundColor = '#6b6b6b'; 
		        fld.style.color = color; 
		        error = fieldname+ " is niet ingevuld.\n"
		    } 
		   else {
		        fld.style.backgroundColor = color;
		        fld.style.color = '#6b6b6b'; 
		    }
		    return error; 
		} 
		
		
		function validateEmail(email, color) {
			
		  var error = "";
		   var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
		   var address = email.value;
		   if(reg.test(address) == false) {
		     error="Uw e-mailadres is niet geldig.\n"
		     email.style.backgroundColor = '#6b6b6b'; 
		     email.style.color = color; 
		   }
		   else{
		   	 email.style.backgroundColor = color;
		   	 email.style.color = '#6b6b6b'; 
		   }
		   return error
		}