function checkInput(url,regio) {

if($F('src').length > 0) {
   var params = 'src=' + $F('src');
   var ajax = new Ajax.Updater(
   {success: 'inputResult'},
   url,
   {method: 'get', parameters: params, onFailure: reportError});
   } else {

/* als de lengte kleiner is dan 0, dan een lege string weergeven */

   var params = 'src=';
   var ajax = new Ajax.Updater(
   {success: 'inputResult'},
   url,
   {method: 'get', parameters: params, onFailure: reportError});
   };
};

/* errorhandling */
function reportError(request) {
   $F('inputResult') = "Error";
}