PHP函数在localhost上运行，但在我的服务器上运行

In a .php page I have the function below. In localhost the JSON response is different than NULL, but when I put the page in on the server (FTP) the JSON response is NULL.

THE CODE

// Check for required parameters
if (isset($_POST["placetype"]) && isset($_POST["placeName"])) {
  $pt = $_POST["placetype"];
  $pn = $_POST["placeName"];
  $dir = 'Pictures/Attractions/'.$pt.'/'.$pn.'/';
  $files = scandir($dir);
  foreach($files as $ind_file) {
    $result[] = array(
      "data" => $ind_file
    );
  sendResponse(200, json_encode($result));
  return true;
}//ifisset
sendResponse(400, 'Invalid request');
return false;

Note: the same folders are on both local and on the server.

Thanks.

See this

$files = scandir($dir);

If you haven't files in $dir, you variable $result will not create and will hold nothing, json will return null. On remote server you haven't files and json_encode return null

I'm guessing the PHP install on your server is not up to date. json_encode() only works with PHP 5 >= 5.2.0.