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<?php $pages = array(); $pages[1] = array('id' => 1, 'parent' => 0, 'name' => 'Hello World'); $pages[2] = array('id' => 1, 'parent' => 1, 'name' => 'Child of Hello World'); $pages[3] = array('id' => 1, 'parent' => 0, 'name' => 'Brother of Hello World'); $pages[4] = array('id' => 4, 'parent' => 2, 'name' => 'Grand-child of Hello World'); $pages[6] = array('id' => 6, 'parent' => 4, 'name' => 'Great-grand-child of Hello World'); $children = array(); foreach($pages as $key => $page){ $parent = (int)$page['parent']; if(!isset($children[$parent])){ $children[$parent] = array(); $children[$parent][$key] = array('id' => $page['id'], 'name' => $page['name']); } } var_dump($children);
Output for 7.1.25 - 7.1.32, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
array(4) { [0]=> array(1) { [1]=> array(2) { ["id"]=> int(1) ["name"]=> string(11) "Hello World" } } [1]=> array(1) { [2]=> array(2) { ["id"]=> int(1) ["name"]=> string(20) "Child of Hello World" } } [2]=> array(1) { [4]=> array(2) { ["id"]=> int(4) ["name"]=> string(26) "Grand-child of Hello World" } } [4]=> array(1) { [6]=> array(2) { ["id"]=> int(6) ["name"]=> string(32) "Great-grand-child of Hello World" } } }
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 array(4) { [0]=> array(1) { [1]=> array(2) { ["id"]=> int(1) ["name"]=> string(11) "Hello World" } } [1]=> array(1) { [2]=> array(2) { ["id"]=> int(1) ["name"]=> string(20) "Child of Hello World" } } [2]=> array(1) { [4]=> array(2) { ["id"]=> int(4) ["name"]=> string(26) "Grand-child of Hello World" } } [4]=> array(1) { [6]=> array(2) { ["id"]=> int(6) ["name"]=> string(32) "Great-grand-child of Hello World" } } }

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