(PHP 5, PHP 7, PHP 8)
array_walk_recursive — Apply a user function recursively to every member of an array
Applies the user-defined callback function to each
element of the array. This function will recurse
into deeper arrays.
arrayThe input array.
callback
Typically, callback takes on two parameters.
The array parameter's value being the first, and
the key/index second.
Note:
If
callbackneeds to be working with the actual values of the array, specify the first parameter ofcallbackas a reference. Then, any changes made to those elements will be made in the original array itself.
arg
If the optional arg parameter is supplied,
it will be passed as the third parameter to the
callback.
Example #1 array_walk_recursive() example
<?php
$sweet = array('a' => 'apple', 'b' => 'banana');
$fruits = array('sweet' => $sweet, 'sour' => 'lemon');
function test_print($item, $key)
{
echo "$key holds $item\n";
}
array_walk_recursive($fruits, 'test_print');
?>The above example will output:
a holds apple b holds banana sour holds lemon
You may notice that the key 'sweet' is never displayed. Any key that holds an
array will not be passed to the function.