如何检查用户是否已登录 php?

本文介绍了如何检查用户是否已登录 php?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我对 PHP 还很陌生，我正在尝试弄清楚如何使用会话来检查用户是否已登录网站，以便他们有权访问特定页面.

I'm pretty new to PHP and I am trying to figure out how to use sessions to check and see if a user is logged into a website so that they would have authorization to access specific pages.

这是否很复杂，还是因为我是菜鸟而无法弄清楚?

Is this something that is complicated or is it because I am a noob that I can't figure it out?

推荐答案

登录并不复杂，但有一些特定的部分几乎所有登录过程都需要.

Logins are not too complicated, but there are some specific pieces that almost all login processes need.

首先，确保在所有需要了解登录状态的页面上启用会话变量，方法是将其放在这些页面的开头:

First, make sure you enable the session variable on all pages that require knowledge of logged-in status by putting this at the beginning of those pages:

session_start();

接下来，当用户通过登录表单提交他们的用户名和密码时，您通常会通过查询包含用户名和密码信息的数据库(例如 MySQL)来检查他们的用户名和密码.如果数据库返回匹配项，则可以设置会话变量以包含该事实.您可能还想包含其他信息:

Next, when the user submits their username and password via the login form, you will typically check their username and password by querying a database containing username and password information, such as MySQL. If the database returns a match, you can then set a session variable to contain that fact. You might also want to include other information:

if (match_found_in_database()) { $_SESSION['loggedin'] = true; $_SESSION['username'] = $username; // $username coming from the form, such as $_POST['username'] // something like this is optional, of course }

然后，在取决于登录状态的页面上，输入以下内容(不要忘记session_start()):

Then, on the page that depends on logged-in status, put the following (don't forget the session_start()):

if (isset($_SESSION['loggedin']) && $_SESSION['loggedin'] == true) { echo "Welcome to the member's area, " . $_SESSION['username'] . "!"; } else { echo "Please log in first to see this page."; }

这些是基本组件.如果您需要 SQL 方面的帮助，网上有很多教程.

Those are the basic components. If you need help with the SQL aspect, there are tutorials-a-plenty around the net.