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<?php $a=array('caption'=>array('c one','c two')); $b=array('photos'=>array('photo one','photo two')); Foreach($a['caption'] as $key => $capt){ $new[$key]['caption'] = $capt; $new[$key]['photos'] = $b['photos'][$key]; } Var_dump($new);
Output for 7.0.0 - 7.0.25, 7.1.0 - 7.1.20, 7.2.5 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array(2) { [0]=> array(2) { ["caption"]=> string(5) "c one" ["photos"]=> string(9) "photo one" } [1]=> array(2) { ["caption"]=> string(5) "c two" ["photos"]=> string(9) "photo two" } }

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