3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array( "key1"=>"value1", "key2"=>null, "key3"=>array( "subkey1"=>null, "subkey2"=>"subvalue2"), "key4"=>null); echo json_encode(replace_null_with_empty_string($arr)); function replace_null_with_empty_string($array) { foreach ($array as $key => $value) { if(is_array($value)) $array[$key] = replace_null_with_empty_string($value); else { if (is_null($value)) $array[$key] = ""; } } return $array; }

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