The filter_id() function is an inbuilt function in PHP which returns the filter ID of a specified filter name. It is used to get the filter id of the particular filter in PHP by using filter_id function by giving the name of the filter as input and get the associated id to it. Syntax:
int filter_id( $filtername )
Parameters: This function accepts single parameter $filtername which is mandatory. It holds the filter name. Return Value: It returns the ID of the filter on success or False if filter doesn’t exist. Note: This function available for PHP 5.2.0 and newer versions. Example 1:
<?php // PHP program to get the filter ID // Use filter_id function to return // the filter id echo (filter_id("validate_email"));
?> |
274
Explanation: validate_email is name of the filter here. The filter_id (“validate_email”) returns 274 as ID of the filter validate_email. Example 2: This example shows all the available filter name and it’s corresponding filter id represented in filter_list() function.
<?php // PHP program to display the filter // list with ID foreach (filter_list() as $id => $filter ) {
echo '<tr><td>' . $filter . '</td><td>'
. filter_id( $filter ) . '</td></tr>' ;
} ?> |
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 |
517 | |
url | 518 |
number_int | 519 |
number_float | 520 |
magic_quotes | 521 |
callback | 1024 |
Explanation: The filter_list() function returning list of filter name. Using filter_id() function id of the filter name is extracted and given output as HTML table component (to represent in better way only). References: http://php.net/manual/en/function.filter-id.php