- array_column: documentation ( source)
- print_r: documentation ( source)
- array_filter: documentation ( source)
- in_array: documentation ( source)
<?php
$_POST['foo'] = '';
$_POST['bar'] = '';
$_POST['baz'] = '';
// fields
$fields = [['Label_Field' => 'foo']];
// just labels
$labels = array_column($fields, 'Label_Field');
// filter $_POST by keys which are in $labels
$data = array_filter($_POST, fn($k) => in_array($k, $labels), ARRAY_FILTER_USE_KEY);
print_r($data);