How to set and get a cookie

$name = 'userid'; 
$value = '87'; 
$expire = strtotime('+1 year'); 
$path = '/'; 
setcookie($name, $value, $expire, $path);

Get the value of a cookie from the browser

$userid = filter_input(INPUT_COOKIE, 'userid', FILTER_VALIDATE_INT); // returns 87, the value stored in the userid field

Delete a cookie from the browser

$expire = strtotime('-1 year'); 
setcookie('userid', '', $expire, '/');

Description

To set a cookie in the user’s browser, you can use the setcookie() function. This function must be called before any HTML output is sent from your application.
A session cookie expires when the user closes the browser. A persistent cookie doesn’t expire until the specified expiration date.
Once a cookie has been set, you can get it the next time the browser requests a page. To do that, you can use the filter_input() function to get it from the superglobal $_COOKIE variable. This variable is an associative array where the cookie name is the key and the cookie value is the value.
To delete a cookie from a browser, set the value to an empty string and the expiration date to a time in the past. Any remaining parameters must have the same values as when the cookie was originally created.