使用ftp_get自动停止从服务器下载图像

<?php
    //user name and password
    $ftp_server="";
    $ftp_user_name="";
    $ftp_user_pass="";

    // define some variables
    $local_file = 'localphoto/';
    $server_file `enter code here`= 'serverPhoto/';


// set up basic connection
$conn_id = ftp_connect($ftp_server);
if($conn_id)
{
    echo "connected";
}
{
 die("Couldn't connect to $ftp_server");
}

ftp_set_option($conn_id, FTP_TIMEOUT_SEC, 18000);

// login with username and password
$login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);

$contents = ftp_nlist($conn_id, $server_file); 
    foreach ($contents as $file) { 

           $cont = explode('/',$file);
           $ret = ftp_get($conn_id, $local_file.$cont[4], $file,  FTP_BINARY);              
}       


// close the connection
ftp_close($conn_id);

?>

am having totally 500 image but it downloads only upto 200 then it stops downloading. In browser the script is keeps running but images has not downloaded. please help me out thanks in advance

you must add set_time_limit(0); for keep Alive Until php script is run i recommended echo something for browser to know php not hangup and keeping Alive

  <?php
   set_time_limit(0);
   //user name and password
   $ftp_server="";
   $ftp_user_name="";
   $ftp_user_pass="";

   // define some variables
   $local_file = 'localphoto/';
   $server_file `enter code here`= 'serverPhoto/';


  // set up basic connection
  $conn_id = ftp_connect($ftp_server);
  if($conn_id)
  {
     echo "connected";
  }else
  {
   die("Couldn't connect to $ftp_server");
  }

  ftp_set_option($conn_id, FTP_TIMEOUT_SEC, 18000);

  // login with username and password
  $login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);

  $contents = ftp_nlist($conn_id, $server_file); 
  foreach ($contents as $file) { 

       $cont = explode('/',$file);
       $ret = ftp_get($conn_id, $local_file.$cont[4], $file,  FTP_BINARY);  
       echo $file."<br>";  //echo something for browser to know php not hangup and keeping Alive
       ob_flush();         
  }       


  // close the connection
  ftp_close($conn_id);