多維數組到PHP中的數組

Question

我有這樣的數組

$category = [
'cat1' => [
    'images/category/cat1/icon1.jpg',
    'images/category/cat1/icon2.jpg',
    'images/category/cat1/icon3.jpg',
],
'cat2' => [
    'images/category/cat2/icon1.jpg',
    'images/category/cat2/icon2.jpg',
    'images/category/cat2/icon3.jpg',
]
];

我想要這樣的數組

$categories = [
'images/category/cat1/icon1.jpg',
'images/category/cat1/icon2.jpg',
'images/category/cat1/icon3.jpg',
'images/category/cat2/icon1.jpg',
'images/category/cat2/icon2.jpg',
'images/category/cat2/icon3.jpg',
];

我試過了，但沒有得到預期的輸出。

$categories = array_map(function($cat){return $cat;},$category);

Answer 1

您可以將call_user_func_array與array_merge結合使用：

$category = call_user_func_array('array_merge', $category);

Answer 2

可以通過array_reduce()和array_merge()

$categories = array_reduce($category, function($old, $new){
    return array_merge($old, $new);
}, array());