$config?=?[
????1?=>?['title'=>?'推薦','code'?=>?1],
????2?=>?['title'=>?'奇聞1','code'?=>?2],
????3?=>?['title'=>?'奇聞2','code'?=>?2],
????4?=>?['title'=>?'搞笑','code'?=>?1]
];

array_walk($config,?function($value,?$key)?use?(&$config){??????//?&?注意

????if($value['code']?==?1){
????????$config[$key]?=?$value['title'];
????}?else?{
????????unset($config[$key]);
????}

});

var_dump($config);

array(3)?{??[1]=>??string(6)?"推薦"??[3]=>??array(2)?{????["title"]=>????string(7)?"奇聞2"????["code"]=>????int(2)??}??[4]=>??string(6)?"搞笑"}