注册成功但不会将信息写入数据库

Question

我遇到这个问题，注册成功了，但它没有把信息写入数据库..为什么？

注册程序代码：

<?php
include_once 'db_connect.php';
include_once 'psl-config.php';

$error_msg = "";

if (isset($_POST['username'], $_POST['email'], $_POST['p'])) {
    // Sanitize and validate the data passed in
    $username = filter_input(INPUT_POST, 'username', FILTER_SANITIZE_STRING);
    $email = filter_input(INPUT_POST, 'email', FILTER_SANITIZE_EMAIL);
    $email = filter_var($email, FILTER_VALIDATE_EMAIL);
    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
        // Not a valid email
        $error_msg .= '<p class="error">The email address you entered is not valid</p>';
    }


    $password = filter_input(INPUT_POST, 'p', FILTER_SANITIZE_STRING);

    // Username validity and password validity have been checked client side.
    // This should should be adequate as nobody gains any advantage from
    // breaking these rules.
    //

    $prep_stmt = "SELECT id FROM members WHERE email = ? LIMIT 1";
    $stmt = $mysqli->prepare($prep_stmt);

   // check existing email  
    if ($stmt) {
        $stmt->bind_param('s', $email);
        $stmt->execute();
        $stmt->store_result();

       if ($stmt->num_rows == 1) {
    $error_msg .= '<p class="error">A user with this email address already exists.</p>';
}
$stmt->close();
    }
    // check existing username
    $prep_stmt = "SELECT id FROM members WHERE username = ? LIMIT 1";
    $stmt = $mysqli->prepare($prep_stmt);

    if ($stmt) {
        $stmt->bind_param('s', $username);
        $stmt->execute();
        $stmt->store_result();

                if ($stmt->num_rows == 1) {
    $error_msg .= '<p class="error">A user with this username  already exists.</p>';
}

$stmt->close();
    }

    // TODO: 
    // We'll also have to account for the situation where the user doesn't have
    // rights to do registration, by checking what type of user is attempting to
    // perform the operation.

    if (empty($error_msg)) {

        // Create salted password 
        $passwordHash = password_hash($password, PASSWORD_BCRYPT);

        // Insert the new user into the database 
        if ($insert_stmt = $mysqli->prepare("INSERT INTO  members (username, email, password) VALUES (?, ?, ?)")) {
  $insert_stmt->bind_param('sss', '$username', '$email', '$passwordHash');
            // Execute the prepared query.
            if (! $insert_stmt->execute()) {
                header('Location: ../error.php?err=Registration failure: INSERT');
            }
        }
        header('Location: ./continue.php');
    }
}

报名表：

<div class="register-form">
    <center><h2>Registration</h2></center>
        <form action="<?php echo esc_url($_SERVER['PHP_SELF']); ?>" 
                method="post" 
                name="registration_form">
            <center><p></p><input type='text' 
                name='username' 
                placeholder="Username"
                id='username' /><br></center>
            <center><p></p><input type="text" name="email" id="email" placeholder="Email" /><br></center>
            <center><p></p><input type="password"
                             name="password"
                             placeholder="Insert Password" 
                             id="password"/><br></center>
            <center><p></p><input type="password" 
                                     name="confirmpwd" 
                                     placeholder="Repeat Password"
                                     id="confirmpwd" /><br></center>
            <center><p></p><input type="submit" class="button"
                   value="Register" 
                   onclick="return regformhash(this.form,
                                   this.form.username,
                                   this.form.email,
                                   this.form.password,
                                   this.form.confirmpwd);" /> </center>
        </form>
        </div>

上次确实有效，但现在却没有，因为服务器有内部错误，所以我不得不重新上传所有文件，还要创建一个新的数据库。我重写了数据库名称和传递，以及应该存在的所有内容，因此它连接到正确的数据库，但是在注册时它不会将信息写入该数据库。

Answer 1

您正在插入文字字符串，即变量名称，而不是值。如果您有唯一约束，这将在第一次失败后失败：

$insert_stmt->bind_param('sss', '$username', '$email', '$passwordHash');

你需要：

$insert_stmt->bind_param('sss', $username, $email, $passwordHash);