function checkinput() {

	CheckForm = document.ThisForm	
	  var errortxt
		
		  var errortxt
		errortxt=''
		  	   
		 if (empty(CheckForm.naam.value)) {
         errortxt = errortxt + "Vul a.u.b. uw naam in.\n\n";
         }   
		 if (empty(CheckForm.adres.value)) {
         errortxt = errortxt + "Vul a.u.b. uw adres in.\n\n";
         }
		 if (empty(CheckForm.postcode.value)) {
         errortxt = errortxt + "Vul a.u.b. uw postcode in.\n\n";
         }
		 if (empty(CheckForm.plaats.value)) {
         errortxt = errortxt + "Vul a.u.b. uw woonplaats in.\n\n";
         }
		 if (empty(CheckForm.telefoon.value)) {
         errortxt = errortxt + "Vul a.u.b. uw telefoon nummer in.\n\n";
         }
		 if (empty(CheckForm.email.value)) {
         errortxt = errortxt + "Vul a.u.b. uw e-mail adres in.\n\n";
		 }
if (errortxt==''){
return true;
	} else {
	alert(errortxt)
	return false;
	}
        
}


function notempty(textObj) {
        if (textObj == "" || textObj == null) {
                return false 
                }
                return true 
        }
function empty(inputStr) {
    if (inputStr == "" || inputStr == null) {
        return true
    }
    return false
}