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<?php $array = Array('Article_1 - Subtype a.ext','Article_1 - Subtype b.ext','Article_2 - Subtype a.ext','Article_2 - Subtype b.ext','Article_2 - Subtype c.ext'); $new_array = array(); foreach($array as $arr) { $exploded_array = explode("-", $arr); $new_array[$exploded_array[0]][] = $arr; } echo "<pre/>"; print_r($new_array); ?><?php $array = Array('Article_1 - Subtype a.ext','Article_1 - Subtype b.ext','Article_2 - Subtype a.ext','Article_2 - Subtype b.ext','Article_2 - Subtype c.ext'); $new_array = array(); foreach($array as $arr) { $exploded_array = explode("-", $arr); $new_array[$exploded_array[0]][] = $arr; } echo "<pre/>"; print_r($new_array); ?>

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