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<?php $arr1= array('a' => "XL"); $arr2= array('a' => "XLd",'b'=>"CDW"); array_walk( $arr2, function(&$val,$key) use ($arr1){ if(isset($arr1[$key])){ $val = $arr1[$key]; } else { $val = ''; } } ); print_r($arr2);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.13
Array ( [a] => XL [b] => )

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148.89 ms | 408 KiB | 5 Q