How to delete COOKIES in PHP?

Question

How can I delete COOKIES in PHP? I know that for sessions you have the session_destroy() but for Cookies how do I?

Answer 1

Use the function itself setcookie() but with negative value in the third parameter (which is the expires), you can also use unset() with the variable $_COOKIE to delete the key in the current execution:

/**
 * Unset cookies
 *
 * @param string $key    Nome do cookie
 * @param string $path   (Opcional) Se definido irá remover o cookie de caminhos especificos
 * @param string $domain (Opcional) Se definido irá remover o cookie de (sub)dominios especificos
 * @param bool $secure   (Opcional) Se definido irá remover o cookie em conexão segura (isto varia conforme o navegador)
 * @return bool
 */
function unsetcookie($key, $path = '', $domain = '', $secure = false)
{
    if (array_key_exists($key, $_COOKIE)) {
        if (false === setcookie($key, null, -1, $path, $domain, $secure)) {
            return false;
        }

        unset($_COOKIE[$key]);
    }

    return true;
}

//Elimina o cookie pro path atual
unsetcookie('meucookie');

//Elimina o cookie pro path raiz
unsetcookie('meucookie', '/');

//Elimina o cookie de um domínio quando estiver em um subdomínio por exemplo: bar.foo.com
unsetcookie('meucookie', '/', 'foo.com');

As in the example of documentation: http://php.net/manual/en/function.setcookie.php#103629

Answer 2

The response of @Guillhermenascimento answers the question very well, but I would like to bring an addition.

When it comes to Cookies, I don’t know if the right way would be to say "Delete Cookies". What is usually done to have the cookie "deleted" is to "invalidate it".

I say this because the most common way is to define a negative value for the parameter $expire. This will make the browser understand that that cookie is "past its expiration date" and will not send it to the server.

Simply put, you delete a cookie like this:

 setcookie('quero_apagar_isso', null, -1);

Logically, one might think that unset($_COOKIE['quero_apagar_isso']) would work, but that’s not true.

The variable $_COOKIE It’s like it’s read-only, because it references something coming from the client.

The only case where unset will work with a variable Super Global is in the variable $_SESSION.

Just reflect: If you used unset($_GET['id']), the parameter id disappear from the url?. Obviously not. Similarly, the Cookie will not cease to exist just because you deleted a value that references it in PHP.

In the same way that you could only delete the parameter id of a url through redirect, you will only be able to delete the Cookie by setting it in a way that the Browser considers invalid.

Answer 3

Do it this way:

<?php

unset($_COOKIE['nome_cookie']);
setcookie('nome_cookie', null, -1, '/');

Answer 4

only:

setcookie('nome_cookie', null, -1, '/');

is necessary to clear cookies.

Answer 5

Easy, my dear. The command is unset($_COOKIE['nomeDoCookie']);

Ready will help you with your problem.

That and good luck!