How to use cookies from a component?

Question

How can I use cookies in a Joomla component?

setcookie( JUtility::getHash('JLOGIN_REMEMBER'), false, time() - 86400, '/' );

Can anybody describe how this works?

Solution

// Get input cookie object
$inputCookie  = JFactory::getApplication()->input->cookie;

// Get cookie data
$value        = $inputCookie->get($name = 'myCookie', $defaultValue = null);

// Check that cookie exists
$cookieExists = ($value !== null);

// Set cookie data
$inputCookie->set($name = 'myCookie', $value = '123', $expire = 0);

// Remove cookie
$inputCookie->set('myCookie', null, time() - 1);

Some rules about $expire value

• its a Unix tinestamp in seconds, like return value of time().
• $expire == 0: cookie lifetime is of browser session.
• $expire < time(): cookie is being deleted (expire set to past). You could remove cookie by setting it's value to null, but apparently IE fails to do so.

Notes

Keep in mind that cookies should be set before headers are sent (usually before output is echoed).

Cookie key and value should be properly escaped

Non-string values

When serializing the value on set (like json_encode($dataNode)), remember to use proper filter to retrieve it later on. Default is cmd, which filters out pretty much anything but a-Z, 0-9 and cracks JSON structure.

// Get cookie data
$encodedString = $inputCookie->get('myCookie', null, $filter = 'string');

// Decode
$values = json_decode($encodedString);

// Encode and Set
$inputCookie->set('myCookie', json_encode($values));

Rererences

• Joomla CMS github repository: JInputCookie::set (very well documented)
• php docs: php.net/setcookie (developer experiences)
• Wikipedia: HTTP Cookies (theory)

Comments

[Timo Huovinen]

The value MUST NOT be an array, joomla does not support subcookies as of now

[Mohd Abdul Mujib]

@piotr_cz On the third line for the check if cookie exists, shouldn't the comparison operator be !== ?