Hello,
PHP filters are used to validate and sanitize external input.
The PHP filter extension has many of the functions needed for checking user input, and is designed to make data validation easier and quicker.
<table>
<tr>
<td>Filter Name</td>
<td>Filter ID</td>
</tr>
<?php
foreach (filter_list() as $id =>$filter) {
echo '<tr><td>' . $filter . '</td><td>' . filter_id($filter) . '</td></tr>';
}
?>
</table>
Many web applications receive external input. External input/data can be:
User input from a form
Cookies
Web services data
Server variables
Database query results