PHP$\u会话变量不起作用_Php_Mysql_Session_Login_Admin

PHP$\u会话变量不起作用

php mysql session login

PHP$\u会话变量不起作用,php,mysql,session,login,admin,Php,Mysql,Session,Login,Admin,最近，我开始制作自己的博客，所以首先我开始制作我的管理面板。在管理面板中，我首先添加了一个管理登录页面。我使用了会话变量。但不知何故，它们没有起作用这是我的登录页面代码： <?php session_start(); if(isset($_POST['submit'])) { $user = $_POST['username']; $pass = $_POST['password']; include('../includes/db_connect.php')

最近，我开始制作自己的博客，所以首先我开始制作我的管理面板。在管理面板中，我首先添加了一个管理登录页面。我使用了会话变量。但不知何故，它们没有起作用

这是我的登录页面代码：

<?php
session_start();
if(isset($_POST['submit']))
{
    $user = $_POST['username'];
    $pass = $_POST['password'];

    include('../includes/db_connect.php');
    $con = mysqli_connect(DB_HOST,DB_USER,DB_PASS,DB_NAME);

    if(empty($user) || empty($pass))
    {
        $msg = 'Missing Information';
    }
    else
    {

        $pass = md5($pass);
        $query = "SELECT * FROM `users` WHERE `username` = '$user' && `password` = '$pass'";
        $result = mysqli_query($con,$query);

        if(mysqli_num_rows($result) == 1)
        {
            while($row = mysqli_fetch_array($result))
            {
                $_SESSION['user_id'] = $row['id'];
                header('Location: index.php');
            }

        }
        else
        {
            $msg = 'Invalid username or password';
        }

    }

}

?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Log In</title>
<link href="../css/login.css" type="text/css" rel="stylesheet" media="screen" />
</head>
<body>
<div id="container">
<form id="login" action="login.php" method="post">
    <h1 id="ff-proof" class="ribbon">Admin Login &nbsp;&nbsp;</h1>
    <fieldset id="inputs">
        <input id="username" name="username" type="text" placeholder="Username" />
        <input id="password" name="password" type="password" placeholder="Password" />
    </fieldset>
    <fieldset id="actions">
        <input type="submit" id="submit" name="submit" value="Log In"/>
        <span style="color: red;"><?php if(isset($msg)){echo $msg;} ?></span>
    </fieldset>
</form>
</div>
</body>
</html>

<?php

session_start();

if(!isset($_SESSION['user_id']))
{
    header('Location: login.php');
}

?>
after that I have my index page code


登录
管理员登录

如果我使用了正确的凭证，它就会起作用。但是在进入管理索引页面后，服务器不再记住会话变量。以下是管理员索引页面代码：

<?php
session_start();
if(isset($_POST['submit']))
{
    $user = $_POST['username'];
    $pass = $_POST['password'];

    include('../includes/db_connect.php');
    $con = mysqli_connect(DB_HOST,DB_USER,DB_PASS,DB_NAME);

    if(empty($user) || empty($pass))
    {
        $msg = 'Missing Information';
    }
    else
    {

        $pass = md5($pass);
        $query = "SELECT * FROM `users` WHERE `username` = '$user' && `password` = '$pass'";
        $result = mysqli_query($con,$query);

        if(mysqli_num_rows($result) == 1)
        {
            while($row = mysqli_fetch_array($result))
            {
                $_SESSION['user_id'] = $row['id'];
                header('Location: index.php');
            }

        }
        else
        {
            $msg = 'Invalid username or password';
        }

    }

}

?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Log In</title>
<link href="../css/login.css" type="text/css" rel="stylesheet" media="screen" />
</head>
<body>
<div id="container">
<form id="login" action="login.php" method="post">
    <h1 id="ff-proof" class="ribbon">Admin Login &nbsp;&nbsp;</h1>
    <fieldset id="inputs">
        <input id="username" name="username" type="text" placeholder="Username" />
        <input id="password" name="password" type="password" placeholder="Password" />
    </fieldset>
    <fieldset id="actions">
        <input type="submit" id="submit" name="submit" value="Log In"/>
        <span style="color: red;"><?php if(isset($msg)){echo $msg;} ?></span>
    </fieldset>
</form>
</div>
</body>
</html>

<?php

session_start();

if(!isset($_SESSION['user_id']))
{
    header('Location: login.php');
}

?>
after that I have my index page code


之后，我有我的索引页代码

但是由于服务器不记得会话变量，我被重定向回登录页面。请帮忙。我试了很多次，但都没能解决问题。

所有文件都在同一个文件夹中吗？你在

index.php

中有什么？试着回显第二个文件中的

$\u会话['user\u id']）

，看看它有什么如果我输入

”或1=1限制1会发生什么--进入用户名字段，使用