php教程

setcookie

(PHP 4, PHP 5, PHP 7)

setcookie — 发送 Cookie

说明

setcookie ( string $name [, string $value = "" [, int $expire = 0 [, string $path = "" [, string $domain = "" [, bool $secure = false [, bool $httponly = false ]]]]]] ) : bool

setcookie() 定义了 Cookie，会和剩下的 HTTP 头一起发送给客户端。 和其他 HTTP 头一样，必须在脚本产生任意输出之前发送 Cookie（由于协议的限制）。 请在产生任何输出之前（包括 <html> 和 <head> 或者空格）调用本函数。

一旦设置 Cookie 后，下次打开页面时可以使用 $_COOKIE 读取。 Cookie 值同样也存在于 $_REQUEST。

参数

» RFC 6265 提供了 setcookie() 每个参数的参考标准。

name

Cookie 名称。

value

Cookie 值。 这个值储存于用户的电脑里，请勿储存敏感信息。 比如 name 是 'cookiename'， 可通过 $_COOKIE['cookiename'] 获取它的值。

expire

Cookie 的过期时间。 这是个 Unix 时间戳，即 Unix 纪元以来（格林威治时间 1970 年 1 月 1 日 00:00:00）的秒数。 也就是说，基本可以用 time() 函数的结果加上希望过期的秒数。 或者也可以用 mktime()。 time()+60*60*24*30 就是设置 Cookie 30 天后过期。 如果设置成零，或者忽略参数， Cookie 会在会话结束时过期（也就是关掉浏览器时）。

Note:

你可能注意到了，expire 使用 Unix 时间戳而非 Wdy, DD-Mon-YYYY HH:MM:SS GMT 这样的日期格式，是因为 PHP 内部作了转换。

path

Cookie 有效的服务器路径。 设置成 '/' 时，Cookie 对整个域名 domain 有效。 如果设置成 '/foo/'， Cookie 仅仅对 domain 中 /foo/ 目录及其子目录有效（比如 /foo/bar/）。 默认值是设置 Cookie 时的当前目录。

domain

Cookie 的有效域名/子域名。 设置成子域名（例如 'www.example.com'），会使 Cookie 对这个子域名和它的三级域名有效（例如 w2.www.example.com）。 要让 Cookie 对整个域名有效（包括它的全部子域名），只要设置成域名就可以了（这个例子里是 'example.com'）。

旧版浏览器仍然在使用废弃的 » RFC 2109， 需要一个前置的点 . 来匹配所有子域名。

secure

设置这个 Cookie 是否仅仅通过安全的 HTTPS 连接传给客户端。 设置成 TRUE 时，只有安全连接存在时才会设置 Cookie。 如果是在服务器端处理这个需求，程序员需要仅仅在安全连接上发送此类 Cookie （通过 $_SERVER["HTTPS"] 判断）。

httponly

设置成 TRUE，Cookie 仅可通过 HTTP 协议访问。 这意思就是 Cookie 无法通过类似 JavaScript 这样的脚本语言访问。 要有效减少 XSS 攻击时的身份窃取行为，可建议用此设置（虽然不是所有浏览器都支持），不过这个说法经常有争议。 PHP 5.2.0 中添加。 TRUE 或 FALSE

返回值

如果在调用本函数以前就产生了输出，setcookie() 会调用失败并返回 FALSE。 如果 setcookie() 成功运行，返回 TRUE。当然，它的意思并非用户是否已接受 Cookie。

范例

发送 Cookie 的几个例子：

Example #1 setcookie() 发送例子

<?php
$value = 'something from somewhere';

setcookie("TestCookie", $value);
setcookie("TestCookie", $value, time()+3600);  /* 1 小时过期  */
setcookie("TestCookie", $value, time()+3600, "/~rasmus/", "example.com", 1);
?>

注意：在发送 Cookie 时，值的部分会被自动 urlencode 编码。收到 Cookie 时，会自动解码，并赋值到可变的 Cookie 名称上。 如果不想被编码，可以使用 setrawcookie() 代替——如果你的 PHP 版本是 5 及以上。 在脚本里查看我们的测试 Cookie 的内容，使用下面的一个例子：

<?php
// 打印一个单独的 Cookie
echo $_COOKIE["TestCookie"];

//  debug/test 查看所有 Cookie 的另一种方式
print_r($_COOKIE);
?>

Example #2 setcookie() 删除例子

要删除一个 Cookie，应该设置过期时间为过去，以触发浏览器的删除机制。 下面的例子展示了如何删除上个例子里的 Cookie：

<?php
// 设置过期时间为一个小时前
setcookie("TestCookie", "", time() - 3600);
setcookie("TestCookie", "", time() - 3600, "/~rasmus/", "example.com", 1);
?>

Example #3 setcookie() 和数组

通过带 array 标记的 Cookie 名称，也可以把 Cookie 设置成数组。 如果有数组元素，可以把它放进 Cookie 里； 脚本接收到时，Cookie 名称里的值会是一个数组：

<?php
// 设置 Cookie
setcookie("cookie[three]", "cookiethree");
setcookie("cookie[two]", "cookietwo");
setcookie("cookie[one]", "cookieone");

// 网页刷新后，打印出以下内容
if (isset($_COOKIE['cookie'])) {
    foreach ($_COOKIE['cookie'] as $name => $value) {
        $name = htmlspecialchars($name);
        $value = htmlspecialchars($value);
        echo "$name : $value <br />\n";
    }
}
?>

以上例程会输出：

three : cookiethree
two : cookietwo
one : cookieone

更新日志

版本 说明
5.5.0 发送给客户端的 Set-Cookie 头现在会包含 Max-Age 属性。
5.2.0 添加 httponly 参数。

注释

Note:

要在调用本函数前输出内容，可以使用输出缓冲：让输出的内容在服务器里缓冲起来， 直至真正发送给浏览器。 可在脚本里调用 ob_start() 和 ob_end_flush()， 或设置 output_buffering php.ini 或服务器配置文件里的配置指令。

Note:

如果 PHP 指令 register_globals 设置成 on，Cookie 值会自动设置成变量。 下面的例子里会存在 $TestCookie。 我们推荐你使用 $_COOKIE。

注意避坑：

  • 在页面（ Cookie 可见的页面）下次刷新前，Cookie 不会生效。 测试 Cookie 是否已经成功设置，需要在下次页面加载时、Cookie 过期前检测。 过期时间是通过 expire 参数设置的。 直接调用 print_r($_COOKIE); 调试检测 Cookie 是个很好的方式。
  • 为同一个参数再次设置 Cookie 前，必须先把它删掉。 如果参数的值是空 string 或 FALSE，并且其他参数和上次调用 setcookie 仍旧一样， 则指定的名称会被远程客户端删除。 内部的实现是：将值设置成 'deleted'，并且过期时间是一年前。
  • 因为设置值成 FALSE 会导致 Cookie 被删除，所以要避免使用布尔值。 代替方式：0 是 FALSE，1 是 TRUE。
  • Cookie 名称可以设置成数组名称，PHP 脚本里会是数组， 但用户系统里储存的是单独分开的 Cookie。 可以考虑使用 explode() 为一个 Cookie 设置多个名称和值。 不建议将 serialize() 用于此处，因为它会导致安全漏洞。

多次调用 setcookie() 会按调用顺序执行。

参见

User Contributed Notes

Anonymous 30-Jan-2019 03:49
I haven't seen this mentioned here and had a lot of issues (and created a lot of stupid hacks) before I figured this out.

If you have a couple of environments for example, and are trying to set cookies on two domains:

example.com (main site)
dev.example.com (dev site)

In this case your (same named) cookies will interfere with each other if you're trying to set cookies with the domain parameter. 

Simply use an empty string for the domain parameter and the cookies will refer to each host separately.

If you use the subdomain www. on the main site this won't be an issue, but without a subdomain you'll have issues with reading each others' cookies.
sergey dot shuchkin at gmail dot com 16-Dec-2018 02:53
Please use code like this to detect cookies support:

<?php

if ( isset($_COOKIE['counter'])) {   
    setcookie('counter', $_COOKIE['counter'] + 1 );
    echo 'Counter='.$_COOKIE['counter'];
} else if ( isset($_GET['set_cookie'])) {
    echo 'Oops! Cookies disabled :(';
} else {
    setcookie('counter', 1);
    header('Location: ?set_cookie=1');
    return;
}

?>
stuff at joneva dot de 20-Sep-2017 09:58
How to store a cookie in php with JSON and read it in JavaScript correctly without using setcookieraw

$defaultActions = array(
                '1' => '0',
                '2' => '0',
                '3' => '0',
                '4' => '0',
                '5' => '0',
                '6' => '0',
                '7' => '0',
                '8' => '0',
                '9' => '0',
                '10' => '0'
            );
$json_str = json_encode($defaultActions);

//delete all cookies
if (isset($_SERVER['HTTP_COOKIE'])) {
    $cookies = explode(';', $_SERVER['HTTP_COOKIE']);
    foreach($cookies as $cookie) {
        $parts = explode('=', $cookie);
        $name = trim($parts[0]);
        setcookie($name, '', time()-1000);
        setcookie($name, '', time()-1000, '/');
    }
}
//setrawcookie("test", $json_str, false,"/",false);

setcookie("test", $json_str, false,"/",false);

?>

<script type="text/javascript">
   
    function getCookie(name) {
        var value = "; " + document.cookie;
        var parts = value.split("; " + name + "=");
        if (parts.length == 2)
            return parts.pop().split(";").shift();
    }
   
    console.log(decodeURIComponent(getCookie('test')));
   
</script>
nacho at casinelli dot com 12-Mar-2017 11:33
It's worth a mention: you should avoid dots on cookie names.

<?php
// this will actually set 'ace_fontSize' name:
setcookie( 'ace.fontSize', 18 );
?>
dont at mail dot me 08-Feb-2017 10:45
> "When deleting a cookie you should assure that the expiration date is in the past, to trigger the removal mechanism in your browser"

This part of the documentation is no longer accurate. On my version of PHP (5.6.28) setting a null, empty string or boolean false value causes the server to ignore your expire date parameter and always sends value "deleted" and expire date 1970-01-01 00:00:01.
lferro9000 at gmail dot com 20-Jan-2017 10:55
Of notice, the cookie when set with a zero expire or ommited WILL not expire when the browser closes.

What happens is that the browser, when closes the window, if it is a well behaved browser, will delete the cookie from the cookie store.

However, the cookie will survive in the server until the garbage collector removes the session, which will happen only when it kicks in and checks the specified session is out of bounds of the setting stated in:

http://php.net/manual/en/session.configuration.php#ini.session.gc-maxlifetime

Please check also:

http://php.net/manual/en/session.security.ini.php

And in case of doubt, PHP runs on the webserver and has no way whatsoever to interact with a browser apart from receiving requests and answering with responses, so assuming that a cookie will be removed from a browser is just an "hint" for the browser. There is no warranty that such will happen as instructed.

That is one of the reasons why the cookie values sent to browsers by some platforms are encrypted and timestamped, to ensure that they are actual and not tampered.
byz 23-Jul-2016 02:57
exmaple with test.com；

setcookie('empty_domain','value',time()+3600,'') 
 equal       test.com

setcookie('test_com_domain','value',time()+3600,'','test.com')  
equal       .test.com

setcookie('dot_test_com_domain','value',time()+3600,'','.test.com') 
 equal       .test.com

ps:   .test.com   has its self    and child domain
dmitry dot koterov at gmail dot com 24-Jun-2015 05:38
Note that at least in PHP 5.5 setcookie() removes previously set cookies with the same name (even if you've set them via header()), so previously fired Set-Cookie headers with e.g. PHPSESSID name are not flushed to the browser. Even headers_list() doesn't see them after session_start():

header("Set-Cookie: PHPSESSID=abc; path=/; domain=.sub.domain.com");
header("Set-Cookie: PHPSESSID=abc; path=/; domain=.domain.com");
print_r(headers_list()); // here you see two Set-Cookie headers with domains for PHPSESSID
session_id('abc');
session_start();
print_r(headers_list()); // here you don't; you see only one Set-Cookie produced by session_start()
ellert at vankoperen dot nl 10-Jul-2014 10:58
Caveat: if you use URL RewriteRules to get stuff like this: domain.com/bla/stuf/etc into parameters, you might run into a hickup when setting cookies.
At least in my setup a change in one of the parameters resulted in the cookie not being 'there' anymore.
The fix is simple: specify the domain. '/' will usualy do fine.
herrkampfgarten at gmail dot com 10-Oct-2012 08:08
Please note that setting the expiry to some timestamp in the past is a common way to get rid of a cookie. However, depending on the value you might set to "invalidate" a cookie immediately, this may pose a threat to the privacy of your user's data, especially when it comes to session cookies.

If you write "0" and "expire-in-the-past" into a session cookie, it remains on the client-side until the clean-up mechanism of the browser hits. (That might be anything from no-time to a very long time. I'm not even thinking of app-based mobile browsers that won't close properly or do their best to ignore standards and RFCs and stuff...)

So, if you have sufficiently messed up your ways of picking up existing session IDs and write-closing their data to your server, the session's data might move from file "sess_(random)" to "sess_0", because that is exactly the identifier that is referred in the cookie.

From now on (at least until your server decides to clean up) there is data laying open wide to anyone requesting the session "0". Which may happen by accident (i.e. another user gains an own "0"-cookie) or malice (i.e. forgery).

Long story short, ALWAYS use an empty string instead of a "0" value for invalidating a session cookie.
walterquez 28-Sep-2012 04:43
Instead of this:
<?php setcookie( "TestCookie", $value, time()+(60*60*24*30) ); ?>

You can this:
<?php setcookie( "TestCookie", $value, strtotime( '+30 days' ) ); ?>
danielpopescu93 at gmail dot com 30-Aug-2012 02:43
Hei, so here is what problem I had, maybe it will help someone in the future:
I couldn't delete a cookie, not even set it a different value. I think that is because it had a name following the rule FirstSecondThird. So it had uppercase letters.
After I modified the name everithing worked.

Another note:
Just for safety you should put what you want to put in the cookie in a var first.
Bachsau 26-Jun-2012 01:49
Want to remove a cookie?

Many people do it the complicated way:
setcookie('name', 'content', time()-3600);

But why do you make it so complicated and risk it not working, when the client's time is wrong? Why fiddle around with time();

Here's the easiest way to unset a cookie:
setcookie('name', 'content', 1);

Thats it.
vanclute at gmail dot com 11-Sep-2011 11:05
I have been tearing my hair out wondering why a cookie would not delete.  Despite countless discussions of reasons this can happen all over the internet, none of them addresses my case.  Here is what was happening:

My cookies have been formed kindof as an array, and the name of the cookie to be deleted is being passed in a variable, so I was using this to attempt to delete the cookie (stripped to the minimum for simplicity of the example):

<?php
    setcookie("$cookiename[id]");
?>

But it simply would not work.  Ultimately what DID work was this:

<?php
    setcookie($cookiename."[id]");
?>

So I had to concatenate the variable to the "element id" and then the cookies deleted without any issue.

I hope this saves someone else from a sleepless night!!

Jonathan
mkmohsinali at gmail dot com 28-Jul-2011 11:01
#cookies.php
/*This code will demonstrate use of cookies with PHP
It is very easy to understand and is better for beginner to
understand and get idea about power of cookies when used
with PHP.Here we give user a form to choose colors he/she
likes for website and when he/she visits site again within one
hour his/her settings are saved and read from cookie
and he/she doesn't have to set the page color and page
text color again.You can change time from 3600
seconds to whatever you deem appropriate in your case.
if you don't understand anything please email me*/

<?php
#checking if form has been submitted
if (isset($_POST['submitted'])){
#if yes (form is submitted) assign values from POST array to variables
$newbgColor=$_POST['bgColor'];
$newtxtColor=$_POST['txtColor'];
#set cookies
setcookie("bgColor",$newbgColor,time()+3600);
setcookie("txtColor",$newtxtColor,time()+3600);

}
#in case user has come for first time and cookies are not set then
if ((!isset($_COOKIE['bgColor']) ) && (!isset($_COOKIE['txtColor']))){
$bgColor = "Black";
$txtColor="White";
}
#if cookies are set then use them
else{
$bgColor = $_COOKIE['bgColor'];
$txtColor = $_COOKIE['txtColor'];
}
?>
<!-- HTML Page-->
<html>
<body bgcolor="<?php echo $bgColor ?>" text="<?php echo $txtColor ?>">
<form action= "<?php echo $_SERVER['PHP_SELF']; ?>" method ="POST">
<p>Body Color:</p>
<select name=bgColor>
<option value ="Red">Red</option>
<option value ="Green" selected>Green</option>
<option value ="Blue">Blue</option>
<option value ="Yellow">Yellow</option>
<option value ="Black">Black</option>
<option value ="Brown">Brown</option>
<option value ="White">White</option>
</select>
<p>Text Color:</p>
<select name=txtColor>
<tion value ="Red">Red</option>
<option value ="Green" selected>Green</option>
<option value ="Blue">Blue</option>
<option value ="Yellow">Yellow</option>
<option value ="Black">Black</option>
<option value ="Brown">Brown</option>
<option value ="White">White</option>
</select>
<input type ="hidden" name="submitted" value="true"></br>
<input type="submit" value="remind">
</form>
</body>
</html>
MrXCol 13-Jul-2011 08:27
If you're having problem with IE not accepting session cookies this could help:

It seems the IE (6, 7, 8 and 9) do not accept the part 'Expire=0' when setting a session cookie. To fix it just don't put any expire at all. The default behavior when the 'Expire' is not set is to set the cookie as a session one.

(Firefox doesn't complains, btw.)
chris at styl dot ee 31-May-2011 08:10
I was searching for a simple example of creating a cookie, storing a random number and updating it on refresh. I couldn't find one so I had to figure it out on my own....

- - - -
One thing to *NOTE* is technically you can't update a cookie, you can only overwrite it with a new one with the same name.

- - - -

This creates a random number, stores it in a cookie, then references it on refresh, checks for duplicates and does necessary correction, then stores it again, rinse and repeat...

<?php
ob_start();
$MaxCount = 4;// set the max of the counter, in my tests "4" = (0,1,2,3) I adjusted below (+1) to get a "real" 4 (0,1,2,3,4) this is in reality 5 keys to humans, you can adjust script to eliminate "0", but my script makes use of the "0"

$random =(rand()%($MaxCount+1));//give me a random number limited by the max, adding "1" because computers start counting at "0"

if(!isset($_COOKIE['random'])){// check if random number cookie is not set
    //echo"not set";
    setcookie('random', $random);//set the cookie for the first time
    }else{
    $lastRandom= $_COOKIE['random']; //hold the last number if it was set before
    if($lastRandom == $random){//some logic to avoid repeats
     if($random < $MaxCount){//if below max, add 1
        $random++;
        //echo "under the max, adding 1, ";   
    }elseif($random >= ($MaxCount-1)){// if for some reason the random number is more than max or equal to it -1, and an additional -1 for max count in initial var (so in reality this -1 from intial max var, and -1 from $random which should be the same number)
            $random--;
            //echo "hit the max, subtracting 1, ";
        }else{
        $random++;
        //echo "no case match, adding 1, ";   
        }
    //echo "(".$lastRandom.", ".$random. "), they matched initally - was it fixed?";
    }else{
    //echo "(".$lastRandom.", ".$random. "), they DO NOT match";
    setcookie('random', $random);   
    }
    //echo"is set: {$_COOKIE['random']}";
}

ob_end_flush();

?>
bocian941 at pawno dot pl 24-Apr-2011 12:51
My 2 functions to use "live cookies":

<?php
    function SetCookieLive($name, $value='', $expire = 0, $path = '', $domain='', $secure=false, $httponly=false)
    {
        $_COOKIE[$name] = $value;
        return setcookie($name, $value, $expire, $path, $domain, $secure, $httponly);
    }

    function RemoveCookieLive($name)
    {
        unset($_COOKIE[$name]);
        return setcookie($name, NULL, -1);
    }
?>
jacobkamphansen at gmail dot com 14-Feb-2011 05:05
I've been pulling my hair for a couple of minutes (read: hours) and finally figured out why setcookie in my case, returned the "headers already sent"-error:

The file in question was orignally saved as ANSI in Notepad and worked flawlessly, but when saved with UTF-8-encoding, it didn't work. So after trying phpDesigner 7, I was able to both save the file in UTF-8 AND remove the BOM (byte-order-mark which is output BEFORE the cookie is set and thereby fails everything).
jdknock (at) gMaIl (dot) com 09-Feb-2011 09:08
IE7 can have trouble with settings cookies that are embedded in an iframe. The problem lies with a W3C standard called Platform for Privacy Preferences or P3P for short.

To overcome, include the header:

header('P3P:CP="IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT"');

before setting the cookie.
RC 24-Sep-2010 07:50
For those of your banging your head as to why a cookie is not present when Internet Explorer 6 prints, the explanation is quite interesting. After a bit of investigation, a cookie with an expiration time other than 0 fails to be passed from IE6 to the server when printing. A cookie with an expiration time of 0 is sent.

Therefore:

setcookie("TestCookie", $value, time()+3600); //will not be sent from Print / Print Preview in IE6

setcookie("TestCookie", $value, 0); //will be sent from Print / Print Preview in IE6

I'll let everyone figure out who's bright idea it was to not send normal expiring cookies when printing in IE6...
Anonymous 10-Sep-2010 03:20
A period in a cookie name (like user.name) seems to show up in the $_COOKIE array as an underscore (so user_name). This means that for example $_COOKIE["user_name"] must be used to read a cookie that has been set with setcookie("user.name" ...), which is already rather confusing.

Furthermore the variable $_COOKIE["user_name"] will retain the value set by setcookie("user.name" ...) and no amount of calling setcookie("user_name" ...) will alter this value. This is rather trivially fixed by clearing the "user.name" cookie, but it can take a while to realize this since there's only "user_name" in $_COOKIE.

Hope this saves someone some time.
jay at w3prodigy dot com 17-May-2010 12:31
You can also delete cookies by supplying setcookie an empty value.

setcookie("w3p_cookie", "");
Eric 01-Nov-2009 10:57
The server my php code is running on has sessions disabled so I am forced to store a fair bit of arbitrary data in cookies.  Using array names was impractical and problematic, so I implemented a splitting routine.  I do not serialize any class instances, just arrays and simple objects.

In a nutshell, when setting a cookie value, I serialize it, gzcompress it, base64 encode it, break it into pieces and store it as a set of cookies.  To fetch the cookie value I get the named piece then iterate through piece names rebuilding the base64 data, then reverse the rest of the process.  The only other trick is deleting the pieces correctly.

Sessions are better, but if they are not available this is a viable alternative.  I chose gz over bz for compression because it looked faster with only slightly worse ratios.

Here is a simplified version of my implementation.  This is a good starting point but is not suitable for most uses.  For example, the domain and path are hard coded and no return values are checked for validity.

<?php
define( 'COOKIE_PORTIONS' , '_piece_' );

function clearpieces( $inKey , $inFirst ) {
    $expire = time()-3600;
   
    for ( $index = $inFirst ; array_key_exists( $inKey.COOKIE_PORTIONS.$index , $_COOKIE ) ; $index += 1 ) {
        setcookie( $inKey.COOKIE_PORTIONS.$index , '' , $expire , '/' , '' , 0 );
        unset( $_COOKIE[$inKey.COOKIE_PORTIONS.$index] );
    }
}

function clearcookie( $inKey ) {
    clearpieces( $inKey , 1 );
    setcookie( $inKey , '' , time()-3600 , '/' , '' , 0 );
    unset( $_COOKIE[$inKey] );
}

function storecookie( $inKey , $inValue , $inExpire ) {
    $decode = serialize( $inValue );
    $decode = gzcompress( $decode );
    $decode = base64_encode( $decode );
   
    $split = str_split( $decode , 4000 );//4k pieces
    $count = count( $split );
   
    for ( $index = 0 ; $index < $count ; $index += 1 ) {
        $result = setcookie( ( $index > 0 ) ? $inKey.COOKIE_PORTIONS.$index : $inKey , $split[$index] , $inExpire , '/' , '' , 0 );
    }
   
    clearpieces( $inKey , $count );
}

function fetchcookie( $inKey ) {
    $decode = $_COOKIE[$inKey];
   
    for ( $index = 1 ; array_key_exists( $inKey.COOKIE_PORTIONS.$index , $_COOKIE ) ; $index += 1 ) {
        $decode .= $_COOKIE[$inKey.COOKIE_PORTIONS.$index];
    }
   
    $decode = base64_decode( $decode );
    $decode = gzuncompress( $decode );
   
    return unserialize( $decode );
}
?>
laffen 27-May-2009 01:49
Note that the $_COOKIE variable not will hold multiple cookies with the same name. It is legitimate to set two cookies with the same name to the same host where the sub domain is different.
<?php
setcookie("testcookie", "value1hostonly", time(), "/", ".example.com", 0, true);
setcookie("testcookie", "value2subdom", time(), "/", "subdom.example.com", 0, true);
?>
The next request from the browser will have both cookies in the $_SERVER['HTTP_COOKIE'] variable, but only one of them will be found in the $_COOKIE variable. Requests to subdom.example.com will have both cookies, while browser request to example.com or www.example.com only sends the cookie with the "value1hostonly" value.

<?php
$kaker = explode(";", $_SERVER['HTTP_COOKIE']);
foreach($kaker as $val){
    $k = explode("=", $val);
    echo trim($k[0]) . " => " . $k[1];
}

// output
testcookie => value1hostonly
testcookie => value2subdom

?>
isooik at gmail-antispam dot com 26-Feb-2008 05:18
Here's a more advanced version of the php setcookie() alternative function:

<?php

    /**
     * A better alternative (RFC 2109 compatible) to the php setcookie() function
     *
     * @param string Name of the cookie
     * @param string Value of the cookie
     * @param int Lifetime of the cookie
     * @param string Path where the cookie can be used
     * @param string Domain which can read the cookie
     * @param bool Secure mode?
     * @param bool Only allow HTTP usage?
     * @return bool True or false whether the method has successfully run
     */
    function createCookie($name, $value='', $maxage=0, $path='', $domain='', $secure=false, $HTTPOnly=false)
    {
        $ob = ini_get('output_buffering');

        // Abort the method if headers have already been sent, except when output buffering has been enabled
        if ( headers_sent() && (bool) $ob === false || strtolower($ob) == 'off' )
            return false;

        if ( !empty($domain) )
        {
            // Fix the domain to accept domains with and without 'www.'.
            if ( strtolower( substr($domain, 0, 4) ) == 'www.' ) $domain = substr($domain, 4);
            // Add the dot prefix to ensure compatibility with subdomains
            if ( substr($domain, 0, 1) != '.' ) $domain = '.'.$domain;

            // Remove port information.
            $port = strpos($domain, ':');

            if ( $port !== false ) $domain = substr($domain, 0, $port);
        }

        // Prevent "headers already sent" error with utf8 support (BOM)
        //if ( utf8_support ) header('Content-Type: text/html; CHARSET=gb2312');

        header('Set-Cookie: '.rawurlencode($name).'='.rawurlencode($value)
                                    .(empty($domain) ? '' : '; Domain='.$domain)
                                    .(empty($maxage) ? '' : '; Max-Age='.$maxage)
                                    .(empty($path) ? '' : '; Path='.$path)
                                    .(!$secure ? '' : '; Secure')
                                    .(!$HTTPOnly ? '' : '; HttpOnly'), false);
        return true;
    }

?>

Regards,
Isaak
cwillard at fastmail dot fm 22-Aug-2007 07:55
If you're looking to set multiple values in your cookie (rather than setting multiple cookies) you might find these useful.

<?php
function build_cookie($var_array) {
  if (is_array($var_array)) {
    foreach ($var_array as $index => $data) {
      $out.= ($data!="") ? $index."=".$data."|" : "";
    }
  }
  return rtrim($out,"|");
}

function break_cookie ($cookie_string) {
  $array=explode("|",$cookie_string);
  foreach ($array as $i=>$stuff) {
    $stuff=explode("=",$stuff);
    $array[$stuff[0]]=$stuff[1];
    unset($array[$i]);
  }
  return $array;
}
?>
Hopefully someone finds these useful.
bluewaterbob 12-Jul-2007 11:51
if you are having problems seeing cookies sometimes or deleting cookies sometimes, despite following the advice below, make sure you are setting the cookie with the domain argument. Set it with the dot before the domain as the examples show: ".example.com".  I wasn't specifying the domain, and finally realized I was setting the cookie when the browser url had the http://www.example.com and later trying to delete it when the url didn't have the www. ie. http://example.com. This also caused the page to be unable to find the cookie when the www. wasn't in the domain.  (When you add the domain argument to the setcookie code that creates the cookie, make sure you also add it to the code that deletes the cookie.)
jonathan dot bergeron at rve dot ulaval dot ca 24-May-2007 12:05
About the delete part, I found that Firefox only remove the cookie when you submit the same values for all parameters, except the date, which sould be in the past. Submiting blank values didn't work for me.

Example :
- set -

<?php setcookie( "name", "value", "future_timestamp", "path", "domain" ); ?>

- delete -
<?php setcookie( "name", "value", "past_timestamp", "path", "domain" ); ?>

Jonathan
mike 26-Mar-2007 08:00
Be careful of using the same cookie name in subdirectories. Setting a simple cookie

<?php setcookie("region", $_GET['set_region']); ?>

both in the root / and for instance in this case /admin/ will create 2 cookies with different paths. In reading the cookies back only the first one is read regardless of path.
21-Mar-2007 02:40
if you only want to do something once per unique visitor, you can test if a cookie is set, and if not, set the cookie and perform the action. This being the poorman's version, it has a problem, where if a user is blocking cookies they will appear as a first time visitor each time. What you can do to avoid this is to set a test cookie first and check that it exists. If it exists, then check to see if your second cookie has been set. If the first one is set, but the second isn't, then you know this is a first time visitor.
gabe at fijiwebdesign dot com 25-Feb-2007 07:25
If you want to delete all cookies on your domain, you may want to use the value of:

<?php $_SERVER['HTTP_COOKIE'] ?>

rather than:

<?php $_COOKIE ?>

to dertermine the cookie names.
If cookie names are in Array notation, eg: user[username]
Then PHP will automatically create a corresponding array in $_COOKIE. Instead use $_SERVER['HTTP_COOKIE'] as it mirrors the actual HTTP Request header.

<?php

// unset cookies
if (isset($_SERVER['HTTP_COOKIE'])) {
    $cookies = explode(';', $_SERVER['HTTP_COOKIE']);
    foreach($cookies as $cookie) {
        $parts = explode('=', $cookie);
        $name = trim($parts[0]);
        setcookie($name, '', time()-1000);
        setcookie($name, '', time()-1000, '/');
    }
}

?>
08-Feb-2007 05:13
something that wasn't made clear to me here and totally confused me for a while was that domain names must contain at least two dots (.), hence 'localhost' is invalid and the browser will refuse to set the cookie! instead for localhost you should use false.

to make your code work on both localhost and a proper domain, you can do this:

<?php

$domain = ($_SERVER['HTTP_HOST'] != 'localhost') ? $_SERVER['HTTP_HOST'] : false;
setcookie('cookiename', 'data', time()+60*60*24*365, '/', $domain, false);

?>
ahmetantmen at msn dot com 19-Jan-2007 03:36
You can be sure about the cookie files contents weren't changed.

<?php

$Seperator = '--';
$uniqueID = 'Ju?hG&F0yh9?=/6*GVfd-d8u6f86hp';
$Data = 'Ahmet '.md5('123456789');

setcookie('VerifyUser', $Data.$Seperator.md5($Data.$uniqueID));

if ($_COOKIE) {
   $Cut = explode($Seperator, $_COOKIE['VerifyUser']);
   if (md5($Cut[0].$uniqueID) === $Cut[1]) {
       $_COOKIE['VerifyUser'] = $Cut[0];
   } else {
       die('Cookie data is invalid!!!');
   }
}

echo $_COOKIE['VerifyUser'];

?>

Create a unique id for your site and create a hash with md5($Data.$uniqueID). Attacker can understant that it must be re-hash after change cookie content.
But doesn't. Because cannot guess your unique id. Seperate your hash and data with seperator and send that cookie. Control that hash of returned value and your unique id's is same returned hash. Otherwise you have to stop attack. Sorry for my poor english!
stovenator at gmail dot com 12-Jan-2007 06:54
If you are having issues with IE7 and setcookie(), be sure to verify that the cookie is set via http for http sites, and https for https site.

Also, if the time is incorrect on your server, IE7 will also disallow those cookies from being set.
05-Jan-2007 01:33
If you ever find yourself in a situation where you need to overwrite a non-PHP application's session cookie, you can do that with the following line:

<?php
header("Set-Cookie: SIDNAME=$overwrite; path=/; secure");
?>

I couldn't get setcookie() to do this for all major web browsers, but manually sending the header did the trick. Note: Remove secure if you aren't mandating SSL connections.
paul nospam AT nospam sitepoint dot com 06-Dec-2006 08:59
Note when setting "array cookies" that a separate cookie is set for each element of the array.

On high traffic sites, this can substantially increase the size of subsequent HTTP requests from clients (including requests for static content on the same domain).

More importantly though, the cookie specification says that browsers need only accept 20 cookies per domain.  This limit is increased to 50 by Firefox, and to 30 by Opera, but IE6 and IE7 enforce the limit of 20 cookie per domain.  Any cookies beyond this limit will either knock out an older cookie or be ignored/rejected by the browser.
hansel at gretel dot com 06-Nov-2006 08:12
The following code snippet combines abdullah's and Charles Martin's examples into a powerful combination function (and fixes at least one bug in the process):

<?php
  function set_cookie_fix_domain($Name, $Value = '', $Expires = 0, $Path = '', $Domain = '', $Secure = false, $HTTPOnly = false)
  {
    if (!empty($Domain))
    {
      // Fix the domain to accept domains with and without 'www.'.
      if (strtolower(substr($Domain, 0, 4)) == 'www.')  $Domain = substr($Domain, 4);
      $Domain = '.' . $Domain;

      // Remove port information.
      $Port = strpos($Domain, ':');
      if ($Port !== false)  $Domain = substr($Domain, 0, $Port);
    }

    header('Set-Cookie: ' . rawurlencode($Name) . '=' . rawurlencode($Value)
                          . (empty($Expires) ? '' : '; expires=' . gmdate('D, d-M-Y H:i:s', $Expires) . ' GMT')
                          . (empty($Path) ? '' : '; path=' . $Path)
                          . (empty($Domain) ? '' : '; domain=' . $Domain)
                          . (!$Secure ? '' : '; secure')
                          . (!$HTTPOnly ? '' : '; HttpOnly'), false);
  }
?>

Basically, if the domain parameter is supplied, it is converted to support a broader range of domains.  This behavior may or may not be desireable (e.g. could be a security problem depending on the server) but it makes cookie handling oh-so-much-nicer (IMO).
adruff at gmail dot com 05-Aug-2006 10:14
If you intend to use persistent cookies (vice session cookies that are deleted when the browser is closed) be aware:
1) Firefox appears to require that you include all paramaters, or it will ignore the expiration and treat the cookie as a session cookie
2) My version of firefox (1.5.0.6) defaults to 'keep cookies until i close firefox' , which essentially makes every cookie a session cookie. This of course sucks for devs, but i suppose is supposed to be a security feature for the end user. If the user wants to configure firefox to respect the expiration date and retain cookies beyond the session, the user must change it to 'keep cookies until they expire'.
gareth at gw126 dot com 05-Jun-2006 07:38
You can use cookies to prevent a browser refresh repeating some action from a form post... (providing the client is cookie enabled!)

<?php
//Flag up repeat actions (like credit card transaction, etc)
if(count($_POST)>0) {
    $lastpost= isset($_COOKIE['lastpost']) ? $_COOKIE['lastpost'] : '';
    if($lastpost!=md5(serialize($_POST))) {
        setcookie('lastpost', md5(serialize($_POST)));
        $_POST['_REPEATED']=0;
    } else {
        $_POST['_REPEATED']=1;
    }
}

//At this point, if $_POST['_REPEATED']==1, then  the user
//has hit the refresh button; so don't do any actions that you don't
//want to repeat!
?>

Hope that helps :)

Gareth
simon at ruderich dot com 01-Aug-2005 02:21
If you want to delete a session cookie, you can do it with this code:

<?php
  session_start();

  // many code

  $sessionName = session_name();
  $sessionCookie = session_get_cookie_params();

  session_destroy();

  setcookie($sessionName, false, $sessionCookie['lifetime'], $sessionCookie['path'], $sessionCookie['domain'], $sessionCookie['secure']);
 ?>

This works also well if the session cookie params or the session name were changed.
terry at scribendi dot com 08-May-2005 07:07
A few comments have suggested using serialize() to set object or array data into a cookie.  There are a couple of reasons to be carefull with that technique:

Security: If the cookie is human readable, then it is also fairly easy for end users to play around with it.  Wrapping your cookie setting and getting in an encryption routine will prevent tampering, and make sure that your cookies don't make any sense to any client-side exploits or other sites they get sent to thanks to browser bugs.

Bulk: If you serialize even a fairly simple class, then you get a lot of data.  Large cookies will make browser requests fat and slow, and some browsers have a limit on cookie size, so think about what data you really need to persist, and create __sleep() and __wakeup() methods to package the data into the shortest possible form.  You can get better and faster results when you write your own __sleep() and __wakup() to implode() or pack() your data, than by using zlib compress() on the serialized object.
Carl V 07-Apr-2005 08:29
If you want to delete all the cookies set by your domain, you may run the following:

<?php
$cookiesSet = array_keys($_COOKIE);
for ($x=0;$x<count($cookiesSet);$x++) setcookie($cookiesSet[$x],"",time()-1);
?>

Very useful when doing logout scripts and the cookie name may have changed (long story).
apex at xepa dot nl 24-Nov-2003 06:59
Note on setting cookies allowing access to sites:

If you are not using something "personal" from the computer that you are sending the cookie too watch out.  Via javascript it is possible to steal cookies from other users.  Thus allowing the stealer to login to your site as another user that might not have access otherwise.  Try to add something like the user's ip in the cookie and allowing access from that ip only with the stored cookie data.

[Editor's note: ... or simply use sessions. You can't be sure that the visitor will use the same IP the next visit. Not even on the next request (thanks to proxy servers)]
30-Sep-2003 04:13
When using your cookies on a webserver that is not on the standard port 80, you should NOT include the :[port] in the "Cookie domain" parameter, since this would not be recognized correctly.
I had the issue working on a project that runs on multiple servers (development, production, etc.). One of the servers is running on a different port (together with other websites that run on the same server but on different ports).
dave at fubra dot com 09-Sep-2003 12:36
There are several characters that dont work correctly if part of the cookie name, I in particular ran into problems using = as part of the cookie name ie/

<?php setcookie('dE4fR=', $foo); ?>

this was as a result of base64_encode() ing a variable to use as the name. The cookie was being set fine but the = is stored as a little square character in the cookie which prevent proper retreival.

The solution for me was to use md5() instead of base64_encode() but any other method which avoids the = sign should also solve the problem
mleer at sp dot nl 19-Dec-2002 02:50
P3P is a good idea. But.
IE 6 features an inadequate definition of third party cookies.
If your site is hosted on server A and your PHP stuff is coming in a framesetting from server B your setcookie-attempts will be blocked when default privacy settings are deployed. Your secondparty-cookie will be regarded as a thirdparty-cookie.

So what you do is not read the P3P-Internet Explorer 6-manual at MS but send a header like

<?php
header('P3P: CP="NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM"');
?>

before doing the setcookie-thing. This will enable your cookie to survive any IE-6 privacy settings.

You won't do this if you're working for some doubleclick institution, because if you do, you... you...well... you are not a very nice person!

CopyRight © 2008-2022 verySource.Com All Rights reserved.　京ICP备17048824号-1　京公网安备：11010502034788