- strpos: documentation ( source)
- filter_var: documentation ( source)
<?php
$_POST = [
'wind_1' => 'hk',
'hamburger_66' => 'foo',
'wind_2' => 'pop',
'wind_25' => 'another'
];
foreach ($_POST as $k => $v) {
if (strpos($k, 'wind_') === 0) {
$key = $k;
}
}
echo filter_var($key, FILTER_SANITIZE_NUMBER_INT);