纠正PHP中的编程错误

时间:2018-04-27 16:21:28

标签: php mysql login error-handling

我最近使用Apache和MySQL安装了PHP。我决定使用PHP为我的网站开发一个登录页面,其中Apache作为Web服务器,MySQL作为数据库用于验证登录凭据。它有5个部分:

  1. config.php 用于连接数据库2. register.php 新用户可以注册自己3. login.php 现有用户可以登录
  2. welcome.php 用户在成功登录后重定向,并且 logout.php 用于退出。
  3. 我使用过程PHP脚本来开发这些页面。这是我的代码:

    的config.php

    <?php
    /* Database credentials. I am running MySQL
    server with default setting (user 'root' with 'root' password) */
    define('DB_SERVER', 'localhost');
    define('DB_USERNAME', 'root');
    define('DB_PASSWORD', 'root');
    define('DB_NAME', 'LoginData');
    
    /* Attempt to connect to MySQL database */
    $link = mysqli_connect(DB_SERVER, DB_USERNAME, DB_PASSWORD, DB_NAME);
    
    // Check connection
    if($mysqli === false){
        die("ERROR: Could not connect. " . $mysqli->connect_error);
    }
    ?>
    

    register.php

    <?php
    // Include config file
    require_once 'config.php';
    
    // Define variables and initialize with empty values
    $username = $password = $confirm_password = "";
    $username_err = $password_err = $confirm_password_err = "";
    
    // Processing form data when form is submitted
    if($_SERVER["REQUEST_METHOD"] == "POST"){
    
        // Validate username
        if(empty(trim($_POST["username"]))){
            $username_err = "Please enter a username.";
        } else{
            // Prepare a select statement
            $sql = "SELECT id FROM users WHERE username = ?";
    
            if($stmt = $mysqli->prepare($sql)){
                // Bind variables to the prepared statement as parameters
                $stmt->bind_param("s", $param_username);
    
                // Set parameters
                $param_username = trim($_POST["username"]);
    
                // Attempt to execute the prepared statement
                if($stmt->execute()){
                    // store result
                    $stmt->store_result();
    
                    if($stmt->num_rows == 1){
                        $username_err = "This username is already taken.";
                    } else{
                        $username = trim($_POST["username"]);
                    }
                } else{
                    echo "Oops! Something went wrong. Please try again later.";
                }
            }
    
            // Close statement
            $stmt->close();
        }
    
        // Validate password
        if(empty(trim($_POST['password']))){
            $password_err = "Please enter a password.";     
        } elseif(strlen(trim($_POST['password'])) < 6){
            $password_err = "Password must have atleast 6 characters.";
        } else{
            $password = trim($_POST['password']);
        }
    
        // Validate confirm password
        if(empty(trim($_POST["confirm_password"]))){
            $confirm_password_err = 'Please confirm password.';     
        } else{
            $confirm_password = trim($_POST['confirm_password']);
            if($password != $confirm_password){
                $confirm_password_err = 'Password did not match.';
            }
        }
    
        // Check input errors before inserting in database
        if(empty($username_err) && empty($password_err) && empty($confirm_password_err)){
    
            // Prepare an insert statement
            $sql = "INSERT INTO users (username, password) VALUES (?, ?)";
    
            if($stmt = $mysqli->prepare($sql)){
                // Bind variables to the prepared statement as parameters
                $stmt->bind_param("ss", $param_username, $param_password);
    
                // Set parameters
                $param_username = $username;
                $param_password = password_hash($password, PASSWORD_DEFAULT); // Creates a password hash
    
                // Attempt to execute the prepared statement
                if($stmt->execute()){
                    // Redirect to login page
                    header("location: login.php");
                } else{
                    echo "Something went wrong. Please try again later.";
                }
            }
    
            // Close statement
            $stmt->close();
        }
    
        // Close connection
        $mysqli->close();
    }
    ?>
    
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Sign Up</title>
        <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.css">
        <style type="text/css">
            body{ font: 14px sans-serif; }
            .wrapper{ width: 350px; padding: 20px; }
        </style>
    </head>
    <body>
        <div class="wrapper">
            <h2>Sign Up</h2>
            <p>Please fill this form to create an account.</p>
            <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
                <div class="form-group <?php echo (!empty($username_err)) ? 'has-error' : ''; ?>">
                    <label>Username</label>
                    <input type="text" name="username"class="form-control" value="<?php echo $username; ?>">
                    <span class="help-block"><?php echo $username_err; ?></span>
                </div>    
                <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
                    <label>Password</label>
                    <input type="password" name="password" class="form-control" value="<?php echo $password; ?>">
                    <span class="help-block"><?php echo $password_err; ?></span>
                </div>
                <div class="form-group <?php echo (!empty($confirm_password_err)) ? 'has-error' : ''; ?>">
                    <label>Confirm Password</label>
                    <input type="password" name="confirm_password" class="form-control" value="<?php echo $confirm_password; ?>">
                    <span class="help-block"><?php echo $confirm_password_err; ?></span>
                </div>
                <div class="form-group">
                    <input type="submit" class="btn btn-primary" value="Submit">
                    <input type="reset" class="btn btn-default" value="Reset">
                </div>
                <p>Already have an account? <a href="login.php">Login here</a>.</p>
            </form>
        </div>    
    </body>
    </html>
    

    的login.php

    <?php
    // Include config file
    require_once 'config.php';
    
    // Define variables and initialize with empty values
    $username = $password = "";
    $username_err = $password_err = "";
    
    // Processing form data when form is submitted
    if($_SERVER["REQUEST_METHOD"] == "POST"){
    
        // Check if username is empty
        if(empty(trim($_POST["username"]))){
            $username_err = 'Please enter username.';
        } else{
            $username = trim($_POST["username"]);
        }
    
        // Check if password is empty
        if(empty(trim($_POST['password']))){
            $password_err = 'Please enter your password.';
        } else{
            $password = trim($_POST['password']);
        }
    
        // Validate credentials
        if(empty($username_err) && empty($password_err)){
            // Prepare a select statement
            $sql = "SELECT username, password FROM users WHERE username = ?";
    
            if($stmt = $mysqli->prepare($sql)){
                // Bind variables to the prepared statement as parameters
                $stmt->bind_param("s", $param_username);
    
                // Set parameters
                $param_username = $username;
    
                // Attempt to execute the prepared statement
                if($stmt->execute()){
                    // Store result
                    $stmt->store_result();
    
                    // Check if username exists, if yes then verify password
                    if($stmt->num_rows == 1){                    
                        // Bind result variables
                        $stmt->bind_result($username, $hashed_password);
                        if($stmt->fetch()){
                            if(password_verify($password, $hashed_password)){
                                /* Password is correct, so start a new session and
                                save the username to the session */
                                session_start();
                                $_SESSION['username'] = $username;      
                                header("location: welcome.php");
                            } else{
                                // Display an error message if password is not valid
                                $password_err = 'The password you entered was not valid.';
                            }
                        }
                    } else{
                        // Display an error message if username doesn't exist
                        $username_err = 'No account found with that username.';
                    }
                } else{
                    echo "Oops! Something went wrong. Please try again later.";
                }
            }
    
            // Close statement
            $stmt->close();
        }
    
        // Close connection
        $mysqli->close();
    }
    ?>
    
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Login</title>
        <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.css">
        <style type="text/css">
            body{ font: 14px sans-serif; }
            .wrapper{ width: 350px; padding: 20px; }
        </style>
    </head>
    <body>
        <div class="wrapper">
            <h2>Login</h2>
            <p>Please fill in your credentials to login.</p>
            <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
                <div class="form-group <?php echo (!empty($username_err)) ? 'has-error' : ''; ?>">
                    <label>Username</label>
                    <input type="text" name="username"class="form-control" value="<?php echo $username; ?>">
                    <span class="help-block"><?php echo $username_err; ?></span>
                </div>    
                <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
                    <label>Password</label>
                    <input type="password" name="password" class="form-control">
                    <span class="help-block"><?php echo $password_err; ?></span>
                </div>
                <div class="form-group">
                    <input type="submit" class="btn btn-primary" value="Login">
                </div>
                <p>Don't have an account? <a href="register.php">Sign up now</a>.</p>
            </form>
        </div>    
    </body>
    </html>
    

    的welcome.php

    <?php
    // Initialize the session
    session_start();
    
    // If session variable is not set it will redirect to login page
    if(!isset($_SESSION['username']) || empty($_SESSION['username'])){
      header("location: login.php");
      exit;
    }
    ?>
    
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Welcome</title>
        <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.css">
        <style type="text/css">
            body{ font: 14px sans-serif; text-align: center; }
        </style>
    </head>
    <body>
        <div class="page-header">
            <h1>Hi, <b><?php echo htmlspecialchars($_SESSION['username']); ?></b>. Welcome to our site.</h1>
        </div>
        <p><a href="logout.php" class="btn btn-danger">Sign Out of Your Account</a></p>
    </body>
    </html>
    

    logout.php

    <?php
    // Initialize the session
    session_start();
    
    // Unset all of the session variables
    $_SESSION = array();
    
    // Destroy the session.
    session_destroy();
    
    // Redirect to login page
    header("location: login.php");
    exit;
    ?>
    

    我的问题是当我打开任何页面时,我看到了这个错误:

      

    警告:mysqli_stmt_close()期望参数1为mysqli_stmt,   第69行的C:\ Apache24 \ htdocs \ login.php中给出的布尔值

    有人可以告诉我如何解决这些错误,以便我可以成功登录我的网站。

1 个答案:

答案 0 :(得分:0)

移动这个

if($stmt = $mysqli->prepare($sql)){
    // Bind variables to the prepared statement as parameters
    $stmt->bind_param("ss", $param_username, $param_password);

    // Set parameters
    $param_username = $username;
    $param_password = password_hash($password, PASSWORD_DEFAULT); // Creates a password hash

    // Attempt to execute the prepared statement
    if($stmt->execute()){
        // Redirect to login page
        header("location: login.php");
    } else{
        echo "Something went wrong. Please try again later.";
    }
    // Close statement
    $stmt->close();
}
//$stmt->close(); put this in the if condition

如果此条件失败,则因为$stmt评估为false,因此您无法对其进行调用。因此,“最简单”的修复方法是只在它通过时调用close。