As it happens, I just wrote an exhaustive article on the subject:
How Not To Kill Your Testability Using Statics

As it happens, I just wrote an exhaustive article on the subject:
How Not To Kill Your Testability Using Statics

As it happens, I just wrote an exhaustive article on the subject:
How Not To Kill Your Testability Using Statics

<?php
$code=rand(1000,9999);
?>

<script>
    function myfun(){ 
        var x = document.getElementById('captcha1').value;
        var y = <?php echo $code  ?>;

        if (x == y) {
            return true;
        }
        else{
            return false;
        }
    }
<script>
<form>
<span-><?php echo $code;?></span>
<input id="captcha1" name="captcha" type="text">
<input id="button" type='submit'  onclick=" return myfun();" value='Submit'>
</form>

Using getenv() function: To obtain the IP address, we utilise the getenv(“REMOTE ADDR”) method.
In PHP, the getenv() method is used to retrieve the values of an environment variable. It is used to return the value of a specific environment variable.

Syntax:

<?php
 $ipaddress = getenv("REMOTE_ADDR") ;
 Echo "Your IP Address is " . $ipaddress;
?>

Determining IP Address using $_SERVER Variable Method: Another method is to use the $_SERVER[‘REMOTE ADDR’] or $_SERVER[‘REMOTE HOST’] variables to obtain the IP Address. The $_SERVER array variables are produced by web servers such as apache and can be utilised in PHP.
$_SERVER[‘REMOTE ADDR’] basically returns the IP address from which the request was submitted to the web server.
Syntax:

<?php
 $ipaddress = $_SERVER['REMOTE_ADDR']
 Echo "Your IP Address is " . $ipaddress;
?>