How to use cookies in php

* The biggest difference between cookies and sessions:

* The cookie is saved in the client browser

* The session is saved on the server, and the client ID saved in the cookie is used for query

* All sessions are based on cookies, so we must first learn how to use php to set cookies for the client

* Let the server remember the visitor

/ /1. Set cookie (name, value, expire)

//The cookie name is also a variable, and it must also follow PHP’s naming rules for variable identifiers

setcookie('username', 'peter zhu',time()+60*10);  //10分钟后过期
setcookie('email', 'peter@php.cn');

//2. View cookie: Use the super global variable $_COOKIE

//Why do we need to do it twice? The first time is to set it, and the second time is to check the new value

echo &#39;用户名: &#39;,$_COOKIE[&#39;username&#39;],&#39;<br>&#39;;
echo &#39;邮箱: &#39;,$_COOKIE[&#39;email&#39;],&#39;<br>&#39;;

//3. Update cookie:

//Turn off the previous set cookie statement first, and refresh it twice to see the new value

setcookie('username','朱老师');

//3. Delete cookie: setcookie()

//Note 1 :Please turn off the previous setting statement

//Note 2: Only the value has been deleted and cannot be accessed anymore, but the cookie variable name still exists

//Method 1: setcookie(name ), only pass cookie name

setcookie('username');

//Method 2: setcookie(name), pass null value

setcookie('username','');

//Method 3: setcookie(name,'',time()-x ): Pass an expired time at will

setcookie('username','',time()-3600);

//5. Physically delete the cookie: unset($_COOKIE[name]), completely destroy the cookie, and it is finally safe

unset($_COOKIE['username']);