more sanity checking

booking.regn_form.inc

@@ -70,6 +70,13 @@ function booking_register_page()
  */
 function _booking_ecclesia_name_autocomplete($string = "") {
   $matches = array();
+
+  if ($string === "") {
+    // Return empty result to the form in json
+    drupal_json_output($matches);
+    return;  
+  }
+
   $sanitised_string = preg_replace("/[^a-zA-Z0-9\s\.']/", '', $string);
   $sanitised_string .= "%";
   //watchdog('booking_debug', "<pre>Autocomplete checking for ecclesia matching:\n@info</pre>", array('@info' => print_r($sanitised_string, true)));