PHP登录表单不工作，我可以做些什么来修复它？_Php_Mysql_Database_Login

PHP登录表单不工作，我可以做些什么来修复它？

php mysql database login

PHP登录表单不工作，我可以做些什么来修复它？,php,mysql,database,login,Php,Mysql,Database,Login,我有以下两个php脚本： config.php： <?php define('DB_SERVER', 'localhost:3306'); define('DB_USERNAME', 'root'); define('DB_PASSWORD', 'password'); define('DB_DATABASE', 'mind3'); $db = mysqli_connect(DB_SERVER,DB_USERNAME,DB_PASSWORD,DB_DATABASE); ?> 以及i

我有以下两个php脚本： config.php：

<?php
define('DB_SERVER', 'localhost:3306');
define('DB_USERNAME', 'root');
define('DB_PASSWORD', 'password');
define('DB_DATABASE', 'mind3');
$db = mysqli_connect(DB_SERVER,DB_USERNAME,DB_PASSWORD,DB_DATABASE);
?>

以及index.php，其中包含登录脚本和表单：

    <?php
require_once 'config.php';
$username=$password='';
$username_err=$password_err='';
if($_SERVER["REQUEST_METHOD"] == "POST"){

    if(empty(trim($_POST["username"]))){
    $username_err = 'Please enter an username!';
    } else{
    $password = trim($_POST['username']);  
    }

    if(empty(trim($_POST["password"]))){
    $pasword_err = "Please enter a password!";
    } else{
    $password = trim($_POST['password']);
    }

    if(empty($username_err) && empty($password_err)){
    $sql = "SELECT username,password FROM members WHERE username = ?";

    if($stmt = mysqli_prepare($link, $sql)){
        mysqli_stmt_bind_param($stmt, "s", $param_username);
        $param_username = $username;
        if(mysqli_stmt_execute($stmt)){
        mysqli_stmt_store_result($stmt);
        if(mysqli_stmt_num_rows($stmt) == 1){
            if(password_verify($password, $hashed_password)){
            session_start();
            $_SESSION['username'] = $username;
            header("location: welcome.php");

            } else{
            $username_err = 'Username/password is wrong!';
        }
        } else{
        echo "Oops! Something went wrong. Please try again later.";
        }
    }
    mysqli_stmt_close($stmt);
    } 
    mysqli_close($link);
} 
}
?>
<!DOCTYPE html>
<html>
<head>
</head>
<body>
    <div class="wrapper">
    <h2>Log in</h2>
    <form action="<?php echo htmlspecialchars ($_SERVER["PHP_SELF"]); ?>" method="post">
        <div class="form-group <?php echo(!empty($username_err)) ? 'has-error' : ''; ?>">
            <input type="text" name="username" class="form-control" placeholder="Username">
            <span class="help-block"><?php echo $username_err; ?></span>
        </div>
        <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
            <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>
    </form>
    </div>
</body>
</html>

问题是，每当我输入数据库中的凭据时，它都不会将我重定向到welcome.php，也不会告诉我密码或用户名错误。但是，当我不输入用户名或密码时，我会得到请输入用户名或密码

我不明白怎么回事。

您将用户名设置为$passwordvariable而不是$username变量

只需将$password=替换为$username=…

您在第10行的第二个代码片段中遇到了一个错误。这是修复的代码片段，请查看代码注释以了解更多信息

    <?php
    require_once 'config.php';
    $username=$password='';
    $username_err=$password_err='';
    if($_SERVER["REQUEST_METHOD"] == "POST"){

    if(empty(trim($_POST["username"]))){
    $username_err = 'Please enter an username!';
    } else{
    //you got error here (was $password)
    $username = trim($_POST['username']);  
    }

    if(empty(trim($_POST["password"]))){
    $pasword_err = "Please enter a password!";
    } else{
    $password = trim($_POST['password']);
    }

    if(empty($username_err) && empty($password_err)){
    $sql = "SELECT username,password FROM members WHERE username = ?";

    if($stmt = mysqli_prepare($link, $sql)){
        mysqli_stmt_bind_param($stmt, "s", $param_username);
        $param_username = $username;
        if(mysqli_stmt_execute($stmt)){
        mysqli_stmt_store_result($stmt);
        if(mysqli_stmt_num_rows($stmt) == 1){
            if(password_verify($password, $hashed_password)){
            session_start();
            $_SESSION['username'] = $username;
            header("location: welcome.php");

            } else{
            $username_err = 'Username/password is wrong!';
        }
        } else{
        echo "Oops! Something went wrong. Please try again later.";
        }
    }
    mysqli_stmt_close($stmt);
    } 
    mysqli_close($link);
} 
}
?>
<!DOCTYPE html>
<html>
<head>
</head>
<body>
    <div class="wrapper">
    <h2>Log in</h2>
    <form action="<?php echo htmlspecialchars ($_SERVER["PHP_SELF"]); ?>" method="post">
        <div class="form-group <?php echo(!empty($username_err)) ? 'has-error' : ''; ?>">
            <input type="text" name="username" class="form-control" placeholder="Username">
            <span class="help-block"><?php echo $username_err; ?></span>
        </div>
        <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
            <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>
    </form>
    </div>
</body>
</html>

您没有正确设置$username的值

更改：

致：

$hashed_password必须有一个值，因为在password_verify中需要它。使用mysqli的bind_result和fetch方法获取所需的值

之后：

加：

增加出口；在标题后。。重定向，以便在重定向调用后不会执行其他代码

更新代码：

此时添加逗号，而不是=username\u err，password\u err=“”；mysqli_prepare$link，$sql您有未定义的$link变量。我猜你是指mysqli_prepare$db，$sql

    <?php
    require_once 'config.php';
    $username=$password='';
    $username_err=$password_err='';
    if($_SERVER["REQUEST_METHOD"] == "POST"){

    if(empty(trim($_POST["username"]))){
    $username_err = 'Please enter an username!';
    } else{
    //you got error here (was $password)
    $username = trim($_POST['username']);  
    }

    if(empty(trim($_POST["password"]))){
    $pasword_err = "Please enter a password!";
    } else{
    $password = trim($_POST['password']);
    }

    if(empty($username_err) && empty($password_err)){
    $sql = "SELECT username,password FROM members WHERE username = ?";

    if($stmt = mysqli_prepare($link, $sql)){
        mysqli_stmt_bind_param($stmt, "s", $param_username);
        $param_username = $username;
        if(mysqli_stmt_execute($stmt)){
        mysqli_stmt_store_result($stmt);
        if(mysqli_stmt_num_rows($stmt) == 1){
            if(password_verify($password, $hashed_password)){
            session_start();
            $_SESSION['username'] = $username;
            header("location: welcome.php");

            } else{
            $username_err = 'Username/password is wrong!';
        }
        } else{
        echo "Oops! Something went wrong. Please try again later.";
        }
    }
    mysqli_stmt_close($stmt);
    } 
    mysqli_close($link);
} 
}
?>
<!DOCTYPE html>
<html>
<head>
</head>
<body>
    <div class="wrapper">
    <h2>Log in</h2>
    <form action="<?php echo htmlspecialchars ($_SERVER["PHP_SELF"]); ?>" method="post">
        <div class="form-group <?php echo(!empty($username_err)) ? 'has-error' : ''; ?>">
            <input type="text" name="username" class="form-control" placeholder="Username">
            <span class="help-block"><?php echo $username_err; ?></span>
        </div>
        <div class="form-group <?php echo (!empty($password_err)) ? 'has-error' : ''; ?>">
            <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>
    </form>
    </div>
</body>
</html>

$password = trim($_POST['username']);

$username = trim($_POST['username']);

if(mysqli_stmt_num_rows($stmt) == 1){

$hashed_password = "";
$username2 = "";

mysqli_stmt_bind_result($stmt, $username2, $hashed_password);
mysqli_stmt_fetch($stmt);

<?php
require_once 'config.php';
$username = $password = '';
$username_err = $password_err = '';
if ($_SERVER["REQUEST_METHOD"] == "POST") {

    if (empty(trim($_POST["username"]))){
        $username_err = 'Please enter an username!';
    }
    else {
        $username = trim($_POST['username']);
    }

    if (empty(trim($_POST["password"]))){
        $pasword_err = "Please enter a password!";
    }
    else {
        $password = trim($_POST['password']);
    }

    if (empty($username_err) && empty($password_err)) {
        $sql = "SELECT username,password FROM members WHERE username = ?";

        if ($stmt = mysqli_prepare($link, $sql)) {
            mysqli_stmt_bind_param($stmt, "s", $param_username);
            $param_username = $username;
            if (mysqli_stmt_execute($stmt)){
                mysqli_stmt_store_result($stmt);
                if (mysqli_stmt_num_rows($stmt) == 1){
                    $hashed_password = "";
                    $username2 = "";

                    mysqli_stmt_bind_result($stmt, $username2, $hashed_password);
                    mysqli_stmt_fetch($stmt);
                    if (password_verify($password, $hashed_password)){

                        $_SESSION['username'] = $username;
                        mysqli_stmt_close($stmt);
                        mysqli_close($link);
                        header("location: welcome.php"); exit();

                    }
                    else{
                        $username_err = 'Username/password is wrong!';
                    }
                }
                else {
                    echo "Oops! Something went wrong. Please try again later.";
                }
            }
            mysqli_stmt_close($stmt);
        }
        mysqli_close($link);
    }
}
?>