function checkEmptyField(fieldName,classNameOk,classNameError) {
	var emptyString = /^\s*$/ ;
	var hightlightClass = "ui-state-error ui-corner-all";
	var normalClass = "ui-widget-content ui-corner-all";
	if(emptyString.test(document.getElementById(fieldName).value)) {
		document.getElementById(fieldName).className = classNameError;
		return true;
	} else {
		document.getElementById(fieldName).className = classNameOk;
		return false;
	}
}
function checkEmailField(fieldName,classNameOk,classNameError) {
	var emailString = /^[^@]+@[^@.]+\.[^@]*\w\w$/ ;
	var hightlightClass = "ui-state-error ui-corner-all";
	var normalClass = "ui-widget-content ui-corner-all";
	if(!emailString.test(document.getElementById(fieldName).value)) {
		document.getElementById(fieldName).className = classNameError;
		return true;
	} else {
		document.getElementById(fieldName).className = classNameOk;
		return false;
	}
}
function validateLidForm() {
	var errs = 0;
	if(checkEmptyField("contact_naam","inputbox","inputbox_error")) { errs += 1; }
	if(checkEmptyField("contact_telefoon","inputbox","inputbox_error")) { errs += 1; }
	if(checkEmptyField("contact_email","inputbox","inputbox_error")) { errs += 1; }
	else if(checkEmailField("contact_email","inputbox","inputbox_error")) { errs += 1; }
	if(checkEmptyField("contact_bericht","inputbox","inputbox_error")) { errs += 1; }
	return (errs==0);
};
function validateBoekForm() {
	var errs = 0;
	if(checkEmptyField("contact_naam","inputbox","inputbox_error")) { errs += 1; }
	if(checkEmptyField("contact_telefoon","inputbox","inputbox_error")) { errs += 1; }
	if(checkEmptyField("contact_email","inputbox","inputbox_error")) { errs += 1; }
	else if(checkEmailField("contact_email","inputbox","inputbox_error")) { errs += 1; }
	if(checkEmptyField("contact_bericht","inputbox","inputbox_error")) { errs += 1; }
	return (errs==0);
};