PHP development basic tutorial - Cookie

1. What are Cookies?

Cookies are often used to identify users. A cookie is a small file that a server leaves on a user's computer. Each time the same computer requests a page through the browser, the cookie will be sent to the computer. With PHP, you can create and retrieve cookie values.

2. How to create a cookie?

The setcookie() function is used to set cookies.

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

Syntax

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

Example: The code is as follows

In the following example, we will create a cookie named "user" and assign it the value "php". We have also specified that this cookie will expire after one minute:

<?php
setcookie("user", "php", time()+60);
?>

You can also set the cookie expiration time in another way

<?php
$expire=time()+60;
setcookie("user", "php",$expire);
?>

3. 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:

The code is as follows

<html>
<head>
<meta charset="utf-8">
<title>php中文网(php.cn)</title>
</head>
<?php
// 输出 cookie 值
echo $_COOKIE["use"];
?>
</body>
</html>

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

The code is as follows:

<html>
<head>
<meta charset="utf-8">
<title>php中文网(php.cn)</title>
</head>
<body>
<?php
//判断cookie数据是否存在
if (isset($_COOKIE["user"]))
	echo "欢迎 " . $_COOKIE["user"] . "!<br>";
else
	echo "普通访客!<br>";
?>
</body>
</html>

4. 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);
?>

Continuing Learning

new file

<?php setcookie("user", "php", time()+60); ?>

submit Reset Code

Automatic operation

PHP development basic tutorial - Cookie

ElementaryImperial CMS enterprise imitation website tutorial

ElementaryNewbies with zero foundation in WordPress build personal blogs and corporate websites

ElementaryUltimate CMS zero-based website building instruction video

ElementaryFront-end project-Shangyou [HTML/CSS/JS technology comprehensive practice]

IntermediateVue3.0 from 0 to build a universal backend management system project practice

ElementaryZero-based front-end course [Vue advanced learning and practical application]

ElementaryWEB front-end tutorial [HTML5+CSS3+JS]

ElementaryQuick introduction to apipost

IntermediateVue3+TypeScript practical tutorial-enterprise-level project practice

ElementaryLet's briefly talk about starting a business in PHP

IntermediateVUE e-commerce project (front-end & back-end dual project actual combat)

ElementaryApipost practical application [api, interface, automated testing, mock]