- array_map: documentation ( source)
- implode: documentation ( source)
<?php
$input = array(
array(
'1' => '2',
'2' => '3'
),
array(
'1' => '3',
'2' => '2'
)
);
echo implode(', ', array_map(function ($entry) {
return $entry['tag_name'];
}, $input));