php - 创建登录页面：提交表单时调用未定义的函数empty()

问题描述

我正在尝试创建一个注册页面，但是当我出于某种原因提交表单时，它会出现此错误

致命错误：未捕获错误：调用 /opt/lampp/htdocs/register.php:16 中的未定义函数 empty() 堆栈跟踪：第 16 行 /opt/lampp/htdocs/register.php 中抛出的 #0 {main}

我的register.php就像

<?php
// Include config file
require_once "config.php";

// Define variables and initialize with empty values

$username = $Name = $Email = $password = $confirm_password = $Phone = "";
$username_err = $Name_err = $Email_err = $password_err = $confirm_password_err = $Phone_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 UID FROM `user details` WHERE username = ?";
        
        if($stmt = mysqli_prepare($link, $sql)){
            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "s", $param_username);
            
            // Set parameters
            $param_username = trim($_POST["username"]);
            
            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){
                /* store result */
                mysqli_stmt_store_result($stmt);
                
                if(mysqli_stmt_num_rows($stmt) == 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
            mysqli_stmt_close($stmt);
        }
    }
    
    // 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(empty($password_err) && ($password != $confirm_password)){
            $confirm_password_err = "Password did not match.";
        }
    }
     // Check input errors before inserting in database
    if(empty($username_err) && empty($Name_err) && empty($Email_err) && empty($password_err) && empty($confirm_password_err)&& empty($Phone_err) ){
        
        // Prepare an insert statement
        $sql= " INSERT INTO      `user details`  ( username, Name, Email, password, Phone) VALUES (?,  ? , ?, ?, ?)";
        
        if($stmt = mysqli_prepare($link, $sql)){
            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "ss" , $param_username,  $param_Name, $param_Email, $param_password, $param_Phone); 
            
            // Set parameters
            $param_username = $username;
            $param_Name = $Name;
            $param_Email = $Email;
            $param_password = password_hash($password, PASSWORD_DEFAULT); // Creates a password hash
            $param_Phone = $Phone;
            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){
                // Redirect to login page
                header("location: login.php");
            } else{
                echo "Something went wrong. Please try again later.";
            }

            // Close statement
            mysqli_stmt_close($stmt);
        }
    }
    
    // Close connection
    mysqli_close($link);
}
?>
            
<!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($Name_err)) ? 'has-error' : ''; ?>">
                <label>Name</label>
                <input type="text" name="Name" class="form-control" value="<?php echo $Name; ?>">
                <span class="help-block"><?php echo $Name_err; ?></span>
            </div>   
           
           <div class="form-group <?php echo (!empty($Email_err)) ? 'has-error' : ''; ?>">
                <label>Email</label>
                <input type="text" name="Email" class="form-control" value="<?php echo $Email; ?>">
                <span class="help-block"><?php echo $Email_err; ?></span>
            </div>   
                        <div class="form-group <?php echo (!empty($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 <?php echo (!empty($Phone_err)) ? 'has-error' : ''; ?>">
                <label>phone</label>
                <input type="text" name="Phone" class="form-control" value="<?php echo $Phone; ?>">
                <span class="help-block"><?php echo $Phone_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>

我的config.php就像

<?php
/* Database credentials. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
define('DB_SERVER', 'localhost');
define('DB_USERNAME', 'root');
define('DB_PASSWORD', '');
define('DB_NAME', 'nlp_portal350k');

/* Attempt to connect to MySQL database */
$link = mysqli_connect(DB_SERVER, DB_USERNAME, DB_PASSWORD, DB_NAME);

// Check connection
if($link === false){
   die("ERROR: Could not connect. " . mysqli_connect_error());
}
?>

现在，当我提交表单时，由于某些原因会出现此错误

警告：mysqli_stmt_bind_param()：类型定义字符串中的元素数与第 74 行 /opt/lampp/htdocs/register.php 中的绑定变量数不匹配出现问题。请稍后再试。

标签： php

php - 创建登录页面：提交表单时调用未定义的函数empty()

问题描述

解决方案

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