3v4l.org

run code in 300+ PHP versions simultaneously
<?php $attributes = array( 'Users' => array( 'Name' => 'Name', ), 'Address' => 'Address', 'Tags' => array( 0 => array( 'Key' => 'Key', 'Value' => 'Value', ), 1 => array( 'Key' => 'Key', ), 2 => array( ) ), ); function deal($array, $prekey){ $res = array(); foreach ($array as $key => $val) { if(is_array($val)){ $tmp = deal($val, $prekey.$key."_"); $res = array_merge($tmp, $res); }else{ $res[$prekey.$key] = $val; } } return $res; } print_r(deal($attributes, ''));

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