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Validate ip address

Let's see how to validate an ip address.
Use the filter_Var() built-in function.
The argument uses the constant FILTER_VALIDATE_IP.

How to validate ip address using filter_var() function

filter_Var('ip',FILTER_VALIDATE_IP);

The first argument uses the ip address, the second uses the constant FILTER_VALIDATE_IP.
As shown in the example, you can change the purpose according to the value of a constant.
Returns true if the ip address is valid or false.
The following example validates ip.

<?php
    $ip = '192.168.0.1';

    $checkIp = filter_Var($ip, FILTER_VALIDATE_IP);

    if($checkIp == true) {
        echo "correct ip";
    } else {
        echo "The ip address is not correct.";
    }
?>

result

This time let's test by entering the wrong ip address.

<?php
    $ip = '192.168.0';

    $checkIp = filter_Var($ip, FILTER_VALIDATE_IP);

    if($checkIp == true) {
        echo "correct ip";
    } else {
        echo "The ip address is not correct.";
    }
?>

result

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