Question

如何循环显示数组键type的值而不循环其他键，因为我有超过500个数组行并减少时间。

$details = array(
    array('year' => '1990'),
    array('year' => '1995'),
    array('condition' => 'working'),
    array('type' => 'bus'),
    array('type' => 'car'),
    array('type' => 'bike'),
);

Answer 1

您可能正在寻找PHP 5.5中引入的array_column（但是这仍然会在整个数组内部循环以收集哪些子数组具有此键）：

<?php

$details = array_column($details, 'year');

print_r($details);

/*
    Array
    (
        [0] => 1990
        [1] => 1995
    )
*/

DEMO

For older versions of PHP the author himself has a polyfill on github

Answer 2

PHP数组

$details = array(
    array('year' => '1990'),
    array('year' => '1995'),
    array('condition' => 'working'),
    array('type' => 'bus'),
    array('type' => 'car'),
    array('type' => 'bike'),
);

创建仅包含“类型”索引的数组

$names = array_map(function ($v)
        { 
            return $v['type']; 
        }, 
        $details);

$names = array_filter($names);      

print_r($names);

输出

Array ( [3] => bus [4] => car [5] => bike )

在PHP中仅循环某些数组键

2 个答案: