php中数组中某个键值为空的时分，不加入到数组

	$data = array();
			if (!empty($_POST['field_id'])) {
				foreach ($_POST['field_id'] as $k => $v) {
					$data[] = array(
						'field_id' => $v, 
						'choice' => isset($_POST['choice'][$k]) ? $_POST['choice'][$k] : '', 
						'uid' => $_POST['uid'],
						'game_id' => $_POST['game_id'],
						'server_id' => $_POST['server_id']
					);  
				}   
			}  

Array
(
    [0] => Array
        (
            [field_id] => 1
            [choice] => 0
            [uid] => 110000110
            [game_id] => 2
            [server_id] => 2
        )

    [1] => Array
        (
            [field_id] => 2
            [choice] => 0
            [uid] => 110000110
            [game_id] => 2
            [server_id] => 2
        )

    [2] => Array
        (
            [field_id] => 3
            [choice] => 1
            [uid] => 110000110
            [game_id] => 2
            [server_id] => 2
        )

)

$data = array();
if (!empty($_POST['field_id'])) {
   foreach ($_POST['choice'] as $k => $v) {
      if($v == '') continue;
      $data[] = array(
          'field_id' => $_POST['field_id'][$k], 
          'choice' => $_POST['choice'][$k], 
          'uid' => $_POST['uid'],
          'game_id' => $_POST['game_id'],
          'server_id' => $_POST['server_id']
      );  
  }   
}