The following example uses Session to determine whether the user is logged in:
PHP session variable is used to store information about the user session (session), or to change the user session (session) setting. Session variables store information for a single user and are available to all pages in the application.
Recommended: php server
functions.php
<?php
function loggedIn(){
//通过 $_SESSION 来判断用户是否登录
if(!$_SESSION['loggd']){
echo'<form action="checkLogin.php" method="post">
<p>
Username:<br>
<input type="text" name="username">
</p>
<p>
Password:<br>
<input type="password" name="username">
</p>
<p>
<input type="submit" name="submit" value="Log In">
</p>
</form>';
}else{ // 登录显示欢迎页面
echo 'Welcome, '.$_SESSION['username'];
} } ?>index.php
<?php
//Start the session
session_start();
//This is a simplified HTML Document
?>
<html>
<head>
<title>My Page</title>
</head>
<body>
<?php
// 引入 functions.php 文件
require_once("functions.php");
//登录状态显示用户名，未登录显示登录表单
logedIn();
?>
</body>
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