The filter_id() function returns the filter ID of provided filter name.
Syntax
filter_id(filtername)
Parameters
filtername − The name of filter to get the ID from.
Return
The filter_id() function returns filter ID on success or FALSE, if the filter does not exist.
Example
<?php
foreach (filter_list() as $id =>$filter) {
echo $filter . "=" . filter_id($filter) . "<br>";
}
?>Output
The following is the output.
int = 257 boolean = 258 float = 259 validate_regexp = 272 validate_domain = 277 validate_url = 273 validate_email = 274 validate_ip = 275 validate_mac = 276 string = 513 stripped = 513 encoded = 514 special_chars = 515 full_special_chars = 522 unsafe_raw = 516 email = 517 url = 518number_int = 519 number_float = 520 magic_quotes = 521 callback = 1024