public function updateData($postData)
{
if ($this->fileLimit == 1) {
if (!isset($postData[$this->field][0])) {
$value = null;
} else {
$value = $postData[$this->field][0];
}
} else {
if (!isset($postData[$this->field][0])) {
$value = json_encode(array());
} else {
$value = json_encode($postData[$this->field]);
}
}
return array($this->field => $value);
}