function?write($file_name,$data,$mode='w'){
if(!in_array($mode,array('w','a','x')))
return?false;
$dir?=?dirname($file_name);
if(!is_dir($dir))
$dir?=?mkdir($dir,0777);
if(!$dir)?return?false;
$file?=?fopen($file_name,$mode);
if(!$file?||?!is_writable($file_name))?return?false;
fwrite($file,$data);
fclose($file);
return?true;
}
echo?write('xx.txt',json_encode($_POST));