Asking for a PHP two-dimensional array the most efficient way to turn one-dimensional arrays

Two-dimensional arrays:

Array(    [0] => Array        (            [cnname] => 巴宝莉        )    [1] => Array        (            [cnname] => 巴宝        ))

The conversion result is

Array('巴宝莉','巴宝');

Try not to use foreach as much as possible with PHP built-in functions

Reply content:

Two-dimensional arrays:

Array(    [0] => Array        (            [cnname] => 巴宝莉        )    [1] => Array        (            [cnname] => 巴宝        ))

The conversion result is

Array('巴宝莉','巴宝');

Try not to use foreach as much as possible with PHP built-in functions

$old = array(array("cnname"=>"巴宝莉"),array("cnname"=>"巴宝"));var_dump(array_column($old,'cnname'));

json_decode(str_replace(array('"cnname":',"{","}"),array('','',''),json_encode($arr)));效率不敢保证。

  
    2135,        'first_name' => 'John',        'last_name' => 'Doe',    ),    array(        'id' => 3245,        'first_name' => 'Sally',        'last_name' => 'Smith',    ),    array(        'id' => 5342,        'first_name' => 'Jane',        'last_name' => 'Jones',    ),    array(        'id' => 5623,        'first_name' => 'Peter',        'last_name' => 'Doe',    )); $first_names = array_column($records, 'first_name');print_r($first_names);?>

Result

Array(    [0] => John    [1] => Sally    [2] => Jane    [3] => Peter)

http://php.net/manual/ja/function.array-column.php

$old = array(array("cnname"=>"巴宝莉"),array("cnname"=>"巴宝"));$new = array();for($i = 0; $i < count($old); $i++){    $new[] = $old[$i]["cnname"];}var_dump($new);

Array_column ($array, ' key ') returns the specified column in the array, which can be used as a one-dimensional array to extract a column of two-dimensional array (5.5 or more to use)
Who used to know, my own notes ~ encountered in the project:

array_map(function($a){return $a['cnname']},$arr)

