Examples
PHP Manual

Sanitization

Example #1 Sanitizing and validating email addresses

<?php
$a 
'[email protected]';
$b 'bogus - at - example dot org';
$c '([email protected])';

$sanitized_a filter_var($aFILTER_SANITIZE_EMAIL);
if (
filter_var($sanitized_aFILTER_VALIDATE_EMAIL)) {
    echo 
"This (a) sanitized email address is considered valid.\n";
}

$sanitized_b filter_var($bFILTER_SANITIZE_EMAIL);
if (
filter_var($sanitized_bFILTER_VALIDATE_EMAIL)) {
    echo 
"This sanitized email address is considered valid.";
} else {
    echo 
"This (b) sanitized email address is considered invalid.\n";
}

$sanitized_c filter_var($cFILTER_SANITIZE_EMAIL);
if (
filter_var($sanitized_cFILTER_VALIDATE_EMAIL)) {
    echo 
"This (c) sanitized email address is considered valid.\n";
    echo 
"Before: $c\n";
    echo 
"After:  $sanitized_c\n";    
}
?>

The above example will output:

This (a) sanitized email address is considered valid.
This (b) sanitized email address is considered invalid.
This (c) sanitized email address is considered valid.
Before: ([email protected])
After: [email protected]


Examples
PHP Manual