从关联数组中提取元素

Question

如何从关联数组中提取元素？

$array = array(
   "smart" => "dog",
   "stupid" => "cat",
   "nasty" => "frog",
   "big" => "elephant"
);

我需要删除带有“nasty”键的元素，将其推送到数组的末尾。我不知道数组中元素的索引。我怎样才能做到这一点？ （我使用的是第一个，第二个，第三个，但是键的名称是不同的，没有用逻辑索引！我需要通过它的键删除元素。）

Answer 1

尝试：

$array = array(
   "first" => "un",
   "second" => "dos",
   "third" => "tres"
);

$second = $array['second'];
unset($array['second']);
$array['second'] = $second;

输出：

array(3) {
  ["first"]=>
  string(2) "un"
  ["third"]=>
  string(4) "tres"
  ["second"]=>
  string(3) "dos"
}

修改

$array = array(
   "first" => "un",
   "second" => "dos",
   "third" => "tres"
);
$output = array();

$order = array('first', 'third', 'second');
foreach ( $order as $key ) {
    if ( isset($output[$key]) ) {
        $output[$key] = $array[$key];
    }
}

Answer 2

$array = array(
   "smart" => "dog",
   "stupid" => "cat",
   "nasty" => "frog",
   "big" => "elephant"
);

$array += array_splice($array, array_search('nasty', array_keys($array)), 1);

print_r($array);

Answer 3

extract($array);怎么样？