php使用session回保存用户登录信息-PHP Tutorial-php.cn

Home

Backend Development

PHP Tutorial

php使用session回保存用户登录信息

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 13, 2016 pm 12:26 PM

gtltsession

php使用session来保存用户登录信息

使用session保存页面登录信息

1、数据库连接配置页面：connectvars.php

<?php//数据库的位置define('DB_HOST', 'localhost');//用户名define('DB_USER', 'root');//口令define('DB_PASSWORD', '19900101');//数据库名define('DB_NAME','test') ;?>

2、登录页面：logIn.php

<?php//插入连接数据库的相关信息require_once 'connectvars.php';//开启一个会话session_start();$error_msg = "";//如果用户未登录，即未设置$_SESSION['user_id']时，执行以下代码if(!isset($_SESSION['user_id'])){    if(isset($_POST['submit'])){//用户提交登录表单时执行如下代码        $dbc = mysqli_connect(DB_HOST,DB_USER,DB_PASSWORD,DB_NAME);        $user_username = mysqli_real_escape_string($dbc,trim($_POST['username']));        $user_password = mysqli_real_escape_string($dbc,trim($_POST['password']));        if(!empty($user_username)&&!empty($user_password)){            //MySql中的SHA()函数用于对字符串进行单向加密            $query = "SELECT user_id, username FROM mismatch_user WHERE username = '$user_username' AND "."password = SHA('$user_password')";            //用用户名和密码进行查询            $data = mysqli_query($dbc,$query);            //若查到的记录正好为一条，则设置SESSION，同时进行页面重定向            if(mysqli_num_rows($data)==1){                $row = mysqli_fetch_array($data);                $_SESSION['user_id']=$row['user_id'];                $_SESSION['username']=$row['username'];                $home_url = 'loged.php';                header('Location: '.$home_url);            }else{//若查到的记录不对，则设置错误信息                $error_msg = 'Sorry, you must enter a valid username and password to log in.';            }        }else{            $error_msg = 'Sorry, you must enter a valid username and password to log in.';        }    }}else{//如果用户已经登录，则直接跳转到已经登录页面    $home_url = 'loged.php';    header('Location: '.$home_url);}?><html>    <head>        <title>Mismatch - Log In</title>        <link rel="stylesheet" type="text/css" href="style.css" />    </head>    <body>        <h3 id="Msimatch-Log-In">Msimatch - Log In</h3>        <!--通过$_SESSION['user_id']进行判断，如果用户未登录，则显示登录表单，让用户输入用户名和密码-->        <?php        if(!isset($_SESSION['user_id'])){            echo '<p class="error">'.$error_msg.'</p>';        ?>        <!-- $_SERVER['PHP_SELF']代表用户提交表单时，调用自身php文件 -->        <form method = "post" action="<?php echo $_SERVER['PHP_SELF'];?>">            <fieldset>                <legend>Log In</legend>                <label for="username">Username:</label>                <!-- 如果用户已输过用户名，则回显用户名 -->                <input type="text" id="username" name="username"                value="<?php if(!empty($user_username)) echo $user_username; ?>" />                <br/>                <label for="password">Password:</label>                <input type="password" id="password" name="password"/>            </fieldset>            <input type="submit" value="Log In" name="submit"/>        </form>        <?php        }        ?>    </body></html>

3、登入页面：loged.php

<?php//使用会话内存储的变量值之前必须先开启会话session_start();//使用一个会话变量检查登录状态if(isset($_SESSION['username'])){    echo 'You are Logged as '.$_SESSION['username'].'<br/>';    //点击&ldquo;Log Out&rdquo;,则转到logOut页面进行注销    echo '<a href="logOut.php"> Log Out('.$_SESSION['username'].')</a>';}/**在已登录页面中，可以利用用户的session如$_SESSION['username']、 * $_SESSION['user_id']对数据库进行查询，可以做好多好多事情*/?>

4、注销session页面：logOut.php(注销后重定向到lonIn.php)

<?php//即使是注销时，也必须首先开始会话才能访问会话变量session_start();//使用一个会话变量检查登录状态if(isset($_SESSION['user_id'])){    //要清除会话变量，将$_SESSION超级全局变量设置为一个空数组    $_SESSION = array();    //如果存在一个会话cookie，通过将到期时间设置为之前1个小时从而将其删除    if(isset($_COOKIE[session_name()])){        setcookie(session_name(),'',time()-3600);    }    //使用内置session_destroy()函数调用撤销会话    session_destroy();}//location首部使浏览器重定向到另一个页面$home_url = 'logIn.php';header('Location:'.$home_url);?>

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

PHP Performance Tuning for High Traffic WebsitesMay 14, 2025 am 12:13 AM

ThesecrettokeepingaPHP-poweredwebsiterunningsmoothlyunderheavyloadinvolvesseveralkeystrategies:1)ImplementopcodecachingwithOPcachetoreducescriptexecutiontime,2)UsedatabasequerycachingwithRedistolessendatabaseload,3)LeverageCDNslikeCloudflareforservin

Dependency Injection in PHP: Code Examples for BeginnersMay 14, 2025 am 12:08 AM

You should care about DependencyInjection(DI) because it makes your code clearer and easier to maintain. 1) DI makes it more modular by decoupling classes, 2) improves the convenience of testing and code flexibility, 3) Use DI containers to manage complex dependencies, but pay attention to performance impact and circular dependencies, 4) The best practice is to rely on abstract interfaces to achieve loose coupling.

PHP Performance: is it possible to optimize the application?May 14, 2025 am 12:04 AM

Yes,optimizingaPHPapplicationispossibleandessential.1)ImplementcachingusingAPCutoreducedatabaseload.2)Optimizedatabaseswithindexing,efficientqueries,andconnectionpooling.3)Enhancecodewithbuilt-infunctions,avoidingglobalvariables,andusingopcodecaching

PHP Performance Optimization: The Ultimate GuideMay 14, 2025 am 12:02 AM

ThekeystrategiestosignificantlyboostPHPapplicationperformanceare:1)UseopcodecachinglikeOPcachetoreduceexecutiontime,2)Optimizedatabaseinteractionswithpreparedstatementsandproperindexing,3)ConfigurewebserverslikeNginxwithPHP-FPMforbetterperformance,4)

PHP Dependency Injection Container: A Quick StartMay 13, 2025 am 12:11 AM

APHPDependencyInjectionContainerisatoolthatmanagesclassdependencies,enhancingcodemodularity,testability,andmaintainability.Itactsasacentralhubforcreatingandinjectingdependencies,thusreducingtightcouplingandeasingunittesting.

Dependency Injection vs. Service Locator in PHPMay 13, 2025 am 12:10 AM

Select DependencyInjection (DI) for large applications, ServiceLocator is suitable for small projects or prototypes. 1) DI improves the testability and modularity of the code through constructor injection. 2) ServiceLocator obtains services through center registration, which is convenient but may lead to an increase in code coupling.

PHP performance optimization strategies.May 13, 2025 am 12:06 AM

PHPapplicationscanbeoptimizedforspeedandefficiencyby:1)enablingopcacheinphp.ini,2)usingpreparedstatementswithPDOfordatabasequeries,3)replacingloopswitharray_filterandarray_mapfordataprocessing,4)configuringNginxasareverseproxy,5)implementingcachingwi

PHP Email Validation: Ensuring Emails Are Sent CorrectlyMay 13, 2025 am 12:06 AM

PHPemailvalidationinvolvesthreesteps:1)Formatvalidationusingregularexpressionstochecktheemailformat;2)DNSvalidationtoensurethedomainhasavalidMXrecord;3)SMTPvalidation,themostthoroughmethod,whichchecksifthemailboxexistsbyconnectingtotheSMTPserver.Impl

See all articles