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<?php $arr = [ "one" => "one", "two" => "two", "group1" => [ "three" => "three", "four" => "four", "group2" => [ "five" => "five", ], ], "group3" => [ "six" => "six", ] ]; function mergeRecursive(array $array, $result = []) { foreach($array as $k => $v) { if(!is_array($v)) $result[] = $v; else $result[] = "$k," . mergeRecursive($v, $result); } return $result; } $result = mergeRecursive($arr); print_r($result);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
Warning: Array to string conversion in /in/jiHg5 on line 27 Warning: Array to string conversion in /in/jiHg5 on line 27 Warning: Array to string conversion in /in/jiHg5 on line 27 Array ( [0] => one [1] => two [2] => group1,Array [3] => group3,Array )
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Array to string conversion in /in/jiHg5 on line 27 Notice: Array to string conversion in /in/jiHg5 on line 27 Notice: Array to string conversion in /in/jiHg5 on line 27 Array ( [0] => one [1] => two [2] => group1,Array [3] => group3,Array )
Output for 7.3.32 - 7.3.33
Array ( [0] => one [1] => two [2] => group1,Array [3] => group3,Array )
preferences:
238.46 ms | 401 KiB | 377 Q