我一直致力于一个与租房有关的项目。访客可以注册或登录，只有登录用户可以添加房屋出租。每个用户都有自己的个人资料，显示他上传出租的用户名，电子邮件和住宿。 我的问题是我无法检索登录用户的电子邮件。另外，在我的MySQL数据库中，我在我的accom（modation）表中使用了一个外键，该表引用了用户的主键（USER-ID）。密钥无法与USER-ID匹配。 任何建议都会非常有用。非常感谢你提前。 发布下面的一些代码：
register.php
<?php include('server.php') ?>
<? php
if (isset($_SESSION['username'])) {
$_SESSION['msg'] = "You're now logged in.";
unset($_SESSION["register.php"];
header('Location: user_index.php');
}
?>
<!DOCTYPE html>
<html>
<link href="https://fonts.googleapis.com/css?family=Eater" rel="stylesheet">
<link rel="stylesheet" type="text/css" href="mystyle.css">
<body>
<p id="pagetitle">Booking Planet </p>
<div class="navbar" id="topnav">
<button onclick="document.getElementById('id01').style.display='block'"
style="width:auto;">Login</button>
<button onclick="document.getElementById('id02').style.display='block'"
style="width:auto;">Register</button>
<a href="#home"> HOME </a>
</div>
<?php
$db = mysqli_connect('localhost', 'root', '', 'registration');
// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$result = mysqli_query($db,"SELECT * FROM accom");
echo "<p> </p>";
echo "<div class='acclist'> Explore some fairytale destinations.. </div>";
echo "<ul>";
while($row = mysqli_fetch_array($result))
{
$image=$row['image'];
$target = "images/".basename($image);
echo "<img src='" . $target . "' width=800 height=500/>";
echo "<li id='title'><b>" . $row['title'] . "</b></li>";
echo "<li> Description: <i>" . $row['description'] . "</i></li>";
echo "<li> Address: <i>". $row['address'] . "</i></li>";
echo "<li> Available from: <i>" . $row['checkin'] . "</i></li>";
echo "<li> Available until: <i>" . $row['checkout'] . "</i></li>";
?><button onclick="document.getElementById('id01').style.display='block'"
type='button' class='bookbtn'>Log-in to book now!</button>
<?php
echo "<li><img src='sepline.png' width=1500 height=75> </li>";}
echo "</ul>";
mysqli_close($db);
?>
</div>
<div id="id01" class="modal">
<? php include('errors.php'); ?>
<form action="" method="post" class="modal-content animate" name="login" >
<div class="logocontainer"> Booking Planet
</div>
<h3> Account Log-in. </h3>
<div class="container">
<? php echo $errors; ?>
<label><b>Username</b></label>
<input type="text" placeholder="Enter Username" name="username" required>
<label><b>Password</b></label>
<input type="password" placeholder="Enter Password" name="password"
required>
<button type="submit" name="login_user">Login</button>
</div>
<div class="container">
<button type="button" class="cancelbtn" id="cncl1">Cancel</button>
</div>
</form>
</div>
<!-- REGISTRATION -->
<div id="id02" class="modal">
<form action="" method="post" class="modal-content animate" name="register"
>
<div class="logocontainer"> Booking Planet
</div>
<h3> Create an account. </h3>
<div class="container">
<label><b>Username</b></label>
<input type="text" placeholder="Enter Username" name="username" required>
<label><b>Name</b></label>
<input type="text" placeholder="Enter your Name!" name="name" required>
<label><b>Surname</b></label>
<input type="text" placeholder="Enter your Surname!" name="surname" required>
<label><b>Password</b></label>
<input type="password" placeholder="Enter Password" name="password" required>
<label><b>Email</b></label>
<input type="email" placeholder="Enter Email" name="email" required>
<div class="avatar"><label>Select your avatar: </label>
<input type="file" name="avatar" accept="image/*" required />
<button type="submit" name="reg_user">Register</button>
</div>
<div class="container">
<button type="button" class="cancelbtn" id="cncl2">Cancel</button>
</div>
</form>
</div>
<script src="myscripts.js"></script>
</body>
</html>
user_index.php ：与register.php非常相似，已经注册或登录的人被重定向。我发布了代码的开头。
<?php include('server.php'); ?>
<?phpinclude('auth.php');
session_start();
if ($_SESSION['username']<1) {
session_destroy();
unset($_SESSION['username']);
header("Location: register.php");
}
$db = mysqli_connect('localhost', 'root', '', 'registration');
// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$result = mysqli_query($db,"SELECT email FROM users WHERE
username='$_SESSION['username']'");
$row = mysqli_fetch_array($result);
$_SESSION['email'] = $result;
$username = $_SESSION['username'];
$_SESSION['id']=$id;
header("Location: server.php");
?>
server.php ：包含注册和登录的验证。此外，链接到数据库。我将跳过验证部分。
<?php
session_start();
$email=$_SESSION['email'];
// initializing variables
$errors = array();
// connect to the database
$db = mysqli_connect('localhost', 'root', '', 'registration');
//...validationon code
//once no errors, register user
if (count($errors) == 0) {
$password = md5($password);//encrypt the password before saving in the
database
$query = "INSERT INTO users (username, email, password, name, surname)
VALUES('$username', '$email', '$password', '$name', '$surname')";
mysqli_query($db, $query);
$_SESSION['username'] = $username;
$_SESSION['email'] = $email;
$_SESSION['success'] = "You are now logged in";
header('Location: user_index.php');
}
}
// LOGIN USER
$msg = '';
if (isset($_POST['login_user'])) {
$username = mysqli_real_escape_string($db, $_POST['username']);
$password = mysqli_real_escape_string($db, $_POST['password']);
if (empty($username)) {
array_push($errors, "Username is required");
}
if (empty($password)) {
array_push($errors, "Password is required");
}
if (count($errors) == 0) {
$password = md5($password);
$query = "SELECT * FROM users WHERE username='$username' AND
password='$password'";
$results = mysqli_query($db, $query);
if (mysqli_num_rows($results) == 1) {
session_start();
$_SESSION['email']=$row['email'];
$_SESSION['username'] = $username;
$_SESSION['email'] = $email;
$_SESSION['id']= $id;
$_SESSION['success'] = "You are now logged in";
header('Location: user_index.php');
}else {
echo $msg;
}
}
}
auth.php
<?php
session_start();
if(!isset($_SESSION["username"])){
echo $errors; }
?>
如果您需要任何其他信息，请随时提出任何问题。 对于文本和代码块，我真的很抱歉。