Wednesday, January 20, 2010

Recipe 8.2. Reading Cookie Values










Recipe 8.2. Reading Cookie Values



8.2.1. Problem


You want to read
the value of a cookie that you've previously set.




8.2.2. Solution


Look in the $_COOKIE
auto-global array, as shown in Example 8-5.


Reading a cookie value



<?php
if (isset($_COOKIE['flavor'])) {
print "You ate a {$_COOKIE['flavor']} cookie.";
}
?>






8.2.3. Discussion


A cookie's value isn't available in $_COOKIE during the request in which the cookie is set. In other words, the
setcookie( )
function doesn't alter the value of $_COOKIE. On subsequent requests, however, each cookie sent back to the server is stored in $_COOKIE. If register_globals is on, cookie values are also assigned to global variables.


When a browser sends a cookie back to the server, it sends only the value. You can't access the cookie's domain, path, expiration time, or secure status through $_COOKIE because the browser doesn't send that to the server.


To print the names and values of all cookies sent in a particular request, loop through the $_COOKIE array, as in Example 8-6.


Reading all cookie values



<?php
foreach ($_COOKIE as $cookie_name => $cookie_value) {
print "$cookie_name = $cookie_value <br/>";
}
?>






8.2.4. See Also


Recipe 8.1 shows how to set cookies; Recipe 8.3 shows how to delete cookies; Recipe 8.12 explains output buffering; Recipe 9.15 for information on register_globals.













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