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Description
bool setcookie(
string $name,
string $value = "",
int $expires_or_options = 0,
string $path = "",
string $domain = "",
bool $secure = false,
bool $httponly = false
)
bool setcookie(string $name, string $value = "", array $options = [])
Once the cookies have been set, they can be accessed on the next page load
with the $_COOKIE array.
Cookie
values may also exist in $_REQUEST.
Parameters
» RFC 6265 provides the normative
reference on how each setcookie parameter is
interpreted.
-
name
-
The name of the cookie.
-
value
-
The value of the cookie. This value is stored on the clients computer;
do not store sensitive information. Assuming the
name is 'cookiename', this
value is retrieved through $_COOKIE['cookiename']
-
expires_or_options
-
The time the cookie expires. This is a Unix timestamp so is
in number of seconds since the epoch.
One way to set this is by adding the number of seconds before the cookie
should expire to the result of calling time.
For instance, time()+60*60*24*30 will set the cookie to
expire in 30 days.
Another option is to use the mktime function.
If set to 0, or omitted, the cookie will expire at
the end of the session (when the browser closes).
Note:
You may notice the expires_or_options parameter takes on a
Unix timestamp, as opposed to the date format Wdy, DD-Mon-YYYY
HH:MM:SS GMT, this is because PHP does this conversion
internally.
-
path
-
The path on the server in which the cookie will be available on.
If set to '/', the cookie will be available
within the entire domain. If set to
'/foo/', the cookie will only be available
within the /foo/ directory and all
sub-directories such as /foo/bar/ of
domain. The default value is the
current directory that the cookie is being set in.
-
domain
-
The (sub)domain that the cookie is available to. Setting this to a
subdomain (such as 'www.example.com') will make the
cookie available to that subdomain and all other sub-domains of it (i.e.
w2.www.example.com). To make the cookie available to the whole domain
(including all subdomains of it), simply set the value to the domain
name ('example.com', in this case).
Older browsers still implementing the deprecated
» RFC 2109 may require a leading
. to match all subdomains.
-
secure
-
Indicates that the cookie should only be transmitted over a
secure HTTPS connection from the client. When set to true, the
cookie will only be set if a secure connection exists.
On the server-side, it's on the programmer to send this
kind of cookie only on secure connection (e.g. with respect to
$_SERVER["HTTPS"]).
-
httponly
-
When true the cookie will be made accessible only through the HTTP
protocol. This means that the cookie won't be accessible by
scripting languages, such as JavaScript. It has been suggested that
this setting can effectively help to reduce identity theft through
XSS attacks (although it is not supported by all browsers), but that
claim is often disputed.
true or false
-
options
-
An associative array which may have any of the keys
expires, path, domain,
secure, httponly and samesite.
If any other key is present an error of level E_WARNING
is generated. The values have the same meaning as described for the
parameters with the same name. The value of the samesite
element should be either None, Lax
or Strict.
If any of the allowed options are not given, their default values are the
same as the default values of the explicit parameters. If the
samesite element is omitted, no SameSite cookie
attribute is set.
Note:
To set a cookie that includes attributes that aren't among the keys listed,
use header.
Return Values
If output exists prior to calling this function,
setcookie will fail and return false. If
setcookie successfully runs, it will return true.
This does not indicate whether the user accepted the cookie.
Examples
The following examples demonstrate some ways to send cookies.
Example #1 setcookie send example
<?php
$value = 'something from somewhere';
setcookie("TestCookie", $value);
setcookie("TestCookie", $value, time()+3600); /* expire in 1 hour */
setcookie("TestCookie", $value, time()+3600, "/~rasmus/", "example.com", true);
?>
Note that the value portion of the cookie will automatically be
urlencoded when you send the cookie, and when it is received, it
is automatically decoded and assigned to a variable by the same
name as the cookie name. If you don't want this, you can use
setrawcookie instead. To see
the contents of our test cookie in a script, simply use one of the
following examples:
Example #2 setcookie delete example
When deleting a cookie you should assure that the expiration date
is in the past, to trigger the removal mechanism in your browser.
Examples follow how to delete cookies sent in previous example:
<?php
// set the expiration date to one hour ago
setcookie("TestCookie", "", time() - 3600);
setcookie("TestCookie", "", time() - 3600, "/~rasmus/", "example.com", 1);
?>
Example #3 setcookie and arrays
You may also set array cookies by using array notation in the
cookie name. This has the effect of setting as many cookies as
you have array elements, but when the cookie is received by your
script, the values are all placed in an array with the cookie's
name:
<?php
// set the cookies
setcookie("cookie[three]", "cookiethree");
setcookie("cookie[two]", "cookietwo");
setcookie("cookie[one]", "cookieone");
// after the page reloads, print them out
if (isset($_COOKIE['cookie'])) {
foreach ($_COOKIE['cookie'] as $name => $value) {
$name = htmlspecialchars($name);
$value = htmlspecialchars($value);
echo "$name : $value <br />\n";
}
}
?>
The above example will output:
three : cookiethree
two : cookietwo
one : cookieone
Note:
Using separator characters such as [ and ]
as part of the cookie name is not compliant to RFC 6265, section 4, but supposed
to be supported by user agents according to RFC 6265, section 5.
Notes
Note:
You can use output buffering to send output prior to the
call of this function, with the overhead of all of your output to the
browser being buffered in the server until you send it. You can do this
by calling ob_start and
ob_end_flush in your script, or setting the
output_buffering configuration directive on in your
php.ini or server configuration files.
Common Pitfalls:
-
Cookies will not become visible until the next loading of a page that
the cookie should be visible for. To test if a cookie was successfully
set, check for the cookie on a next loading page before the cookie
expires. Expire time is set via the
expires_or_options
parameter. A nice way to debug the existence of cookies is by
simply calling print_r($_COOKIE);.
-
Cookies must be deleted with the same parameters as they were set with.
If the
value argument is an empty string, and all other arguments
match a previous call to setcookie, then the cookie with the specified
name will be deleted from the remote client.
This is internally achieved by setting value to 'deleted' and expiration
time in the past.
-
Because setting a cookie with a value of
false will try to delete the cookie,
you should not use boolean values. Instead, use 0 for false
and 1 for true.
-
Cookies names can be set as array names and will be available to your
PHP scripts as arrays but separate cookies are stored on the user's
system. Consider explode to set one cookie with
multiple names and values. It is not recommended to use
serialize for this purpose, because it can result
in security holes.
Multiple calls to setcookie are performed in the order called.
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