PHP array_filter与get_class过滤器

Question

I have an array of objects, and I want to check if a certain classname is in it. So I tried:

$all_classnames = array_filter($obj_array, 'get_class');
$found = in_array("classname_to_test", $all_classnames);

Only, $all_classnames still holds the original object array instead of an array of classnames (through get_class). Am I missing something here?

Answer 1

You want to use array_map (which transforms the input array based on the callback function) instead of array_filter :

$all_classnames = array_map('get_class', $obj_array);

Note that array_map takes its arguments in the reverse order than the other array functions that use a callback because PHP.

Answer 2

This is not how the array_filter function works. It just filters your array if the callback returns false it will remove the element from the array.

What you need is array_map

$all_classnames = array_map('get_class', $obj_array);