登錄表單，單擊提交后錯誤500

Question

登錄表單單擊提交后出現錯誤500大家好，我們在php課程中有一個小組作業，我們應該在PHP和MySQL中設計一個登錄系統。 我們編寫了表單，PHP腳本，創建了數據庫，並且一切正常，除了當您按下提交按鈕時輸入在數據庫中指定的用戶名和密碼時，它使我們進入500內部錯誤頁面。 該代碼位於/ login文件夾中名為index.php的文件中，它應授予對父文件夾中文件的訪問權限。 就這個：

<?php
// Initialize the session
session_start();


// Check if the user is already logged in, if yes then redirect him to welcome page
if(isset($_SESSION["loggedin"]) && $_SESSION["loggedin"] === true){
    header("location:../accessgranted.php");
    exit;
}

// Include config file
require_once "db.php";

// Define variables and initialize with empty values
$username = $password = "";
$username_err = $password_err = "";
$username_ph = "Enter Username";
$password_ph = "Enter password";

// Processing form data when form is submitted
if($_SERVER["REQUEST_METHOD"] == "POST"){

    // Check if username is empty quoted th trim function because it caused the same 500 error when trying to run the login page
    if(empty/*(trim*/($_POST["username"]/*)*/)){
        $username_err = "Entrez votre nom d'utilisateur";
    } else{
        $username = trim($_POST["username"]);
    }

    // Check if password is empty
    if(empty/*(trim*/($_POST["password"]/*)*/)){
        $password_err = "Entrez votre mot de passe";
    } else{
        $password = trim($_POST["password"]);
    }

    // Validate credentials
    if(!empty($username) && !empty($password)){
        // Prepare a select statement
        $sql = "SELECT id, username, password FROM Users WHERE username = ?";

        if($stmt = mysqli_prepare($con, $sql)){

            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "s", $param_username);

            // Set parameters
            $param_username = $username;

            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){


                // Store result
                mysqli_stmt_store_result($stmt);

                // Check if username exists, if yes then verify password
                if(mysqli_stmt_num_rows($stmt) == 1){                    
                    // Bind result variables
                    mysqli_stmt_bind_result($stmt, $id, $username, $hashed_password);

                    if(mysqli_stmt_fetch($stmt)){

                        if(password_verify($password, $hashed_password)){

                            // Password is correct, so start a new session
                            session_start();

                            // Store data in session variables
                            $_SESSION["loggedin"] = true;
                            $_SESSION["id"] = $id;
                            $_SESSION["username"] = $username;                            

                            // Redirect user to welcome page
                            header("location: ../accessgranted.php");

                        } else{
                            // Display an error message if password is not valid
                            $password_err = "The password you entered was not valid.";
                        }
                    }//added
                } 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
        mysqli_stmt_close($stmt);
    }

    // Close connection
    mysqli_close($con);
}

?>

<!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>
   <center> 
        <h1>Connection</h1>
        <h2>Login Assignment</h2>
        <div class="wrapper">
        <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
            <div class="form-group <?php echo (!empty($username_err)) ? 'has-error' : ''; ?>">
                <p align="left">Username</p>
                <input type="text" name="username" class="form-control" value="<?php echo $username; ?>" placeholder="<?= $username_ph?>">
                <span class="help-block"><?php echo $username_err; ?></span>
            </div>    
            <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
                <p align="left">Password</p>
                <input type="password" name="password" class="form-control" placeholder="<?= $password_ph?>" align="left">
                <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>  </center>  
</body>
</html>

我們必須在周日之前移交它，因此將非常感謝您的幫助

Answer 1

每當遇到500錯誤時，由於忘記了逗號，點，方括號和SQL查詢，您就在語法上犯了錯誤。

Answer 2

檢查php.ini文件中的error_reporting ， display_errors和display_startup_errors設置。 它們應分別設置為E_ALL和"On" 。 您還可以在腳本的開頭更改這些設置（ display_startup_errors除外），以便在運行時進行設置。

error_reporting(E_ALL);
ini_set('display_errors', 'On');

之后，重新啟動服務器。

並檢查腳本中引起的錯誤。

登錄表單，單擊提交后錯誤500

問題描述

2 個解決方案

解決方案1
0 2018-11-30 07:41:27

解決方案2
0 已采納 2018-11-30 08:05:41

登錄表單，單擊提交后錯誤500

問題描述

2 個解決方案

解決方案1 0 2018-11-30 07:41:27

解決方案2 0 已采納 2018-11-30 08:05:41

解決方案1
0 2018-11-30 07:41:27

解決方案2
0 已采納 2018-11-30 08:05:41