<html><body>function myfunction(&$value,$key){$value="yellow";}$a=array("a"=>"red","b"=>"green","c"=>"blue");array_walk($a,"myfunction");print_r($a);</body><!-- Mirrored from www.w3schools.com/php7/phptryit.asp?filename=tryphp_func_array_walk3 by HTTrack Website Copier/3.x [XR&CO'2014], Wed, 05 Jun 2019 13:40:41 GMT --></html>