Filter and sanitize data with PHP

filter_var.php

<?php
// VALIDATIONS
filter_var($integerNumber, FILTER_VALIDATE_INT); // verify if variable is an integer number
filter_var("127.0.0.1", FILTER_VALIDATE_IP); // verify if is an IP code
filter_var("test@mail.com", FILTER_VALIDATE_EMAIL); // verify if is a correct email
filter_var("https://domain.ext/", FILTER_VALIDATE_URL); // verify if is a correct url
filter_var("true", FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE); // verify if is a boolean value
filter_var("123.45", FILTER_VALIDATE_FLOAT); // verify if is a float number

//SANITIZE DATA
$string = filter_var("<h1>Hi there</h1>", FILTER_SANITIZE_STRING); // sanitize an string. removed html code form string
$sanitized_string = filter_var("<h1>Hello, World!</h1>", FILTER_SANITIZE_FULL_SPECIAL_CHARS); // out: &lt;h1&gt;Hello, World!&lt;/h1&gt;
$sanitized_email = filter_var("test@@domain.com", FILTER_SANITIZE_EMAIL); // out: test@domain.com
$sanitized_url = filter_var("https://www.domain.ext/<script>", FILTER_SANITIZE_URL); // out: https://www.domain.ext/
$sanitized_int = filter_var("123abc", FILTER_SANITIZE_NUMBER_INT); // out: 123


// SOME UTILS VALIDATIONS

// IPV4 Validation
$ip = "192.168.1.1";
if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4)) {
    echo "The IP address (IPv4) is valid.";
} else {
    echo "The IP address (IPv4) is not valid.";
}


// IPV6 Validation
$ip = "2001:0db8:85a3:0000:0000:8a2e:0370:7334";
$options = array(
    'flags' => FILTER_FLAG_IPV6
);
if (filter_var($ip, FILTER_VALIDATE_IP, $options)) {
    echo "The IP address (IPv6) is valid.";
} else {
    echo "The IP address (IPv6) is not valid.";
}

// Validate a number range
$options = array(
    'options' => array(
        'min_range' => 1,
        'max_range' => 100,
    )
);
$int = 50;
if (filter_var($int, FILTER_VALIDATE_INT, $options)) {
    echo "The number is inside the range.";
} else {
    echo "The number is not inside the range.";
}

// Validate a negative integer number
$int = 25;
if (filter_var($int, FILTER_VALIDATE_INT, array("options" => array("min_range" => 0)))) {
    echo "The number is a negative integer number.";
} else {
    echo "The number is not a negative integer number.";
}

// Validate a correct domain
$domain = "example.com";
if (filter_var($domain, FILTER_VALIDATE_DOMAIN, FILTER_FLAG_HOSTNAME)) {
    echo "El dominio es válido.";
} else {
    echo "El dominio no es válido.";
}