setcookieSend a cookie
&reftitle.description;
boolsetcookiestringnamestringvalue""intexpires0stringpath""stringdomain""boolsecure&false;boolhttponly&false;boolsetcookiestringnamestringvalue""arrayoptions[]setcookie defines a cookie to be sent along with the
rest of the HTTP headers. Like other headers, cookies must be sent
before any output from your script (this is a
protocol restriction). This requires that you place calls to this function
prior to any output, including <html> and
<head> tags as well as any whitespace.
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.
&reftitle.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
The time the cookie expires. This is a Unix timestamp so is
in number of seconds since the epoch. In other words, you'll
most likely set this with the time function
plus the number of seconds before you want it to expire. Or
you might use mktime.
time()+60*60*24*30 will set the cookie to
expire in 30 days. If set to 0, or omitted, the cookie will expire at
the end of the session (when the browser closes).
You may notice the expires 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. Added in PHP 5.2.0.
&true; or &false;
options
An associative array which may have any of the keys
expires, path, domain,
secure, httponly and samesite.
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.
&reftitle.returnvalues;
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.
&reftitle.examples;
Some examples follow how to send cookies:
<function>setcookie</function> send example
]]>
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 if you are using PHP 5. To see
the contents of our test cookie in a script, simply use one of the
following examples:
]]>
<function>setcookie</function> 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:
]]>
<function>setcookie</function> 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:
$value) {
$name = htmlspecialchars($name);
$value = htmlspecialchars($value);
echo "$name : $value \n";
}
}
?>
]]>
&example.outputs;
&reftitle.changelog;
&Version;&Description;7.3.0
An alternative signature supporting an options
array has been added. This signature supports also setting of the
SameSite cookie attribute.
5.5.0
A Max-Age attribute is now included in the Set-Cookie header sent to
the client.
5.2.0
The httponly parameter was added.
&reftitle.notes;
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.
If the PHP directive register_globals
is set to on then cookie values will also be made into
variables. In our examples below, $TestCookie will
exist. It's recommended to use $_COOKIE.
Common Pitfalls:
Cookies will not become visible until the next loading of a page that
the cookie should be visible for. To test if a cookie was successfully
set, check for the cookie on a next loading page before the cookie
expires. Expire time is set via the expires
parameter. A nice way to debug the existence of cookies is by
simply calling print_r($_COOKIE);.
Cookies must be deleted with the same parameters as they were set with.
If the value argument is an empty string, or &false;, 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 to one year in 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.
&reftitle.seealso;
headersetrawcookiecookies sectionRFC 6265RFC 2109