Удалите базовый ключ массива здесь
$res= Array (
'key1' => Array ( 'title' => 'Title', 'visible' => 1 ,'order' => 0 ) ,
'key2' => Array ( 'title' => 'Title' ,'visible' => 1 ,'order' => 1 ) ,
'key3' => Array ( 'title' => 'Title' ,'visible' => 1 ,'order' => 2 ) ,
'key4' => Array ( 'title' => 'Title' ,'visible' => 1 ,'order' => 3 ) ,
'key5' => Array ( 'title' => 'Title' ,'visible' => 1 ,'order' => 4 ),
'key6' => Array ( 'title' => 'Title' ,'visible' => 1 ,'order' => 5 ) ,
'key7' => Array ( 'title' => 'Title' ,'visible' => 1 ,'order' => 6 ) ,
);
echo "<pre>";
echo "Before Array<br>";
print_r($res);
unset($res['key4']);
echo "After Array<br>";
print_r($res);
Вывод здесь
Перед массивом
Array( [key1] => Array
(
[title] => Title
[visible] => 1
[order] => 0
)
[key2] => Array
(
[title] => Title
[visible] => 1
[order] => 1
)
[key3] => Array
(
[title] => Title
[visible] => 1
[order] => 2
)
[key4] => Array
(
[title] => Title
[visible] => 1
[order] => 3
)
[key5] => Array
(
[title] => Title
[visible] => 1
[order] => 4
)
[key6] => Array
(
[title] => Title
[visible] => 1
[order] => 5
))
[key7] => Array
(
[title] => Title
[visible] => 1
[order] => 6
))
После массива
Array([key1] => Array
(
[title] => Title
[visible] => 1
[order] => 0
)
[key2] => Array
(
[title] => Title
[visible] => 1
[order] => 1
)
[key3] => Array
(
[title] => Title
[visible] => 1
[order] => 2
)
[key5] => Array
(
[title] => Title
[visible] => 1
[order] => 4
)
[key6] => Array
(
[title] => Title
[visible] => 1
[order] => 5
)
[key7] => Array
(
[title] => Title
[visible] => 1
[order] => 6
))