PHP注册表格打印错误

Question

完成制作php / mysql登录系统。 我还制作了一个可以使用的注册系统，但是如果电子邮件/用户名已经注册，或者输入中的用户名或密码丢失等，我需要使其在html中打印出错误。

现在，它会自动消失，并在空白页上打印出错误消息。

看起来像这样：

        if(empty($_POST['password'])) 
    { 
        die("Please enter a password");
    } 

我已经试过了：

 $errors = array();
if(empty($_POST['password'])) 
{ 
    $errors[] = 'Please enter a password';
} 

然后将其打印到html中。 但是它将忽略密码输入，而只是注册用户帐户（使用加密的密码，在phpmyadmin中）。

似乎必须以某种方式死亡，但是我应该怎么做？

这是整个代码：

<?php 
require("*mysql_connection file*"); 


if(!empty($_POST)) 
{ 

    if(empty($_POST['username'])) 
    { 
        die("Please enter a username."); 
    } 

     $errors = array();
    if(empty($_POST['password'])) 
    { 
        $errors[] = 'Please enter your password';
    } 

    if(!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) 
    { 
        die("Invalid E-Mail Address"); 
    } 

    $query = " 
        SELECT 
            1 
        FROM users 
        WHERE 
            username = :username 
    "; 

    $query_params = array( 
        ':username' => $_POST['username'] 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: " . $ex->getMessage()); 
    } 

    $row = $stmt->fetch(); 

    if($row) 
    { 
        die("This username is already in use"); 
    } 

    $query = " 
        SELECT 
            1 
        FROM users 
        WHERE 
            email = :email 
    "; 

    $query_params = array( 
        ':email' => $_POST['email'] 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: " . $ex->getMessage()); 
    } 

    $row = $stmt->fetch(); 

    if($row) 
    { 
        die("Email already registered.");
    } 

    $query = " 
        INSERT INTO users ( 
            username, 
            password, 
            salt, 
            email 
        ) VALUES ( 
            :username, 
            :password, 
            :salt, 
            :email 
        ) 
    "; 

    $salt = dechex(mt_rand(0, 2147483647)) . dechex(mt_rand(0, 2147483647)); 


    $password = hash('sha256', $_POST['password'] . $salt); 

    for($round = 0; $round < 65536; $round++) 
    { 
        $password = hash('sha256', $password . $salt); 
    } 

    $query_params = array( 
        ':username' => $_POST['username'], 
        ':password' => $password, 
        ':salt' => $salt, 
        ':email' => $_POST['email'] 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 

        die("Failed to run query: " . $ex->getMessage()); 
    } 

    header("Location: *login page*"); 
    die("Redirecting to *login page*"); 
} 

？>

Answer 1

<?php 
require("*mysql_connection file*"); 


if(!empty($_POST)) 
{ 

    if(empty($_POST['username'])) 
    { 
        die("Please enter a username."); 
    } 

     $errors = array();
    if(empty($_POST['password'])) 
    { 
        $errors[] = 'Please enter your password';
    } 

    if(!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) 
    { 
        die("Invalid E-Mail Address"); 
    } 

    $query = " 
        SELECT 
            1 
        FROM users 
        WHERE 
            username = :username 
    "; 

    $query_params = array( 
        ':username' => $_POST['username'] 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: " . $ex->getMessage()); 
    } 

    $row = $stmt->fetch(); 

    if($row) 
    { 
        die("This username is already in use"); 
    } 

    $query = " 
        SELECT 
            1 
        FROM users 
        WHERE 
            email = :email 
    "; 

    $query_params = array( 
        ':email' => $_POST['email'] 
    ); 

    try 
    { 
        $stmt = $db->prepare($query); 
        $result = $stmt->execute($query_params); 
    } 
    catch(PDOException $ex) 
    { 
        die("Failed to run query: " . $ex->getMessage()); 
    } 

    $row = $stmt->fetch(); 

    if($row) 
    { 
        die("Email already registered.");
    } 

    $query = " 
        INSERT INTO users ( 
            username, 
            password, 
            salt, 
            email 
        ) VALUES ( 
            :username, 
            :password, 
            :salt, 
            :email 
        ) 
    "; 

    $salt = dechex(mt_rand(0, 2147483647)) . dechex(mt_rand(0, 2147483647)); 


    $password = hash('sha256', $_POST['password'] . $salt); 

    for($round = 0; $round < 65536; $round++) 
    { 
        $password = hash('sha256', $password . $salt); 
    } 

    $query_params = array( 
        ':username' => $_POST['username'], 
        ':password' => $password, 
        ':salt' => $salt, 
        ':email' => $_POST['email'] 
    ); 


    if (empty($errors)) { /********* EDITS ***********/

        try 
        { 
            $stmt = $db->prepare($query); 
            $result = $stmt->execute($query_params); 
        } 
        catch(PDOException $ex) 
        { 

            die("Failed to run query: " . $ex->getMessage()); 
        } 

    }/********* EDITS ***********/

    header("Location: *login page*"); 
    die("Redirecting to *login page*"); 
} 
?>

这远非最佳，但我无法重写您的整个代码。 主要说明是使用openssl_random_pseudo_bytes而不是您自己的东西来补充盐，或者您可以仅从mcrypt函数系列中删除IV。

Answer 2

尝试这个 ：-

if(""== trim($_POST['password']))
    { 
            die("Please enter a password");
    } 
else //password is entered
{
//your code
}