What does Cookie mean in PHP?-PHP Problem-php.cn

What does Cookie mean in PHP?

Guanhui

Release： 2023-03-01 17:20:01

Original

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Cookie is often used to identify users. It is a small file left by the server on the user's computer. Whenever the same computer requests a page through the browser, this computer will send the Cookie. Through PHP, the user can Create and retrieve cookie values.

What does Cookie mean in PHP?

Recommended tutorial: "PHP Cookie-based Shopping Cart Module Design"

How to create a cookie?

The setcookie() function is used to set cookies.

Note: The setcookie() function must be located before the tag.

Syntax

setcookie(name, value, expire, path, domain);

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Example 1

In the following example, we will create a cookie named "user" and assign it the value "runoob". We also specify that this cookie expires after one hour:

<?php
setcookie("user", "runoob", time()+3600);
?>
<html>
.....

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Note: The cookie value is automatically URL-encoded when sending the cookie and automatically decoded when retrieved. (To prevent URL encoding, use setrawcookie() instead.)

Example 2

You can also set the cookie expiration time in another way. This may be simpler than using seconds.

<?php
$expire=time()+60*60*24*30;
setcookie("user", "runoob", $expire);
?>
<html>
.....

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In the above example, the expiration time is set to one month (60 seconds * 60 minutes * 24 hours * 30 days).

How to retrieve the value of Cookie?

PHP’s $_COOKIE variable is used to retrieve the value of the cookie.

In the following example, we retrieve the value of the cookie named "user" and display it on the page:

<?php
// 输出 cookie 值
echo $_COOKIE["user"];
// 查看所有 cookie
print_r($_COOKIE);
?>

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In the following example, we use isset() function to confirm whether the cookie has been set:

<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
</head>
<body>
<?php
if (isset($_COOKIE["user"]))
    echo "欢迎 " . $_COOKIE["user"] . "!<br>";
else
    echo "普通访客!<br>";
?>
</body>
</html>

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How to delete cookies?

When deleting a cookie, you should change the expiration date to a point in time in the past.

Deleted instance:

<?php
// 设置 cookie 过期时间为过去 1 小时
setcookie("user", "", time()-3600);
?>

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Recommended tutorial: "PHP Tutorial"

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