allow 0 for ISINT

Florian Schaal

2016-01-10 e2c08e59a23fe28a2816c985422f796b9c6b39b0

 interface/lib/classes/tform_base.inc.php

@@ -979,7 +979,7 @@
            break;
         case 'ISINT':
            if(function_exists('filter_var') && $field_value < 2147483647) {
               if($field_value != '' && filter_var($field_value, FILTER_VALIDATE_INT) === false) {
               if($field_value != '' && filter_var($field_value, FILTER_VALIDATE_INT, array("options" => array('min_range'=>0))) === false) {
                  $errmsg = $validator['errmsg'];
                  if(isset($this->wordbook[$errmsg])) {
                     $this->errorMessage .= $this->wordbook[$errmsg]."<br />\r\n";