注册表单 PHP - Register form PHP

我是PHP和MySQL的初学者，我正在尝试为我目前正在从事的项目创建这个注册表单，这是PHP脚本，顺便说一句。如果有很多错误，那是因为我刚刚开始！

我遇到的问题是它不会检查数据库是否匹配电子邮件或用户名，因为如果匹配，它应该拒绝。

PHP代码：

    <?php
//register php
error_reporting(0);
$regUsername = $_POST['reg-username'];
$regEmail = $_POST['reg-email'];
$regPassword = $_POST['reg-password'];
if(isset($regUsername) && isset($regEmail) && isset($regPassword)){
        $connect = mysql_connect('localhost', 'root', '');
        $selectDB = mysql_select_db('supermazad');
        $query = mysql_query("INSERT INTO users (username, email, password) VALUES ('$regUsername', '$regEmail', '$regPassword')");
        $checkIfSame = mysql_query("SELECT * FROM users WHERE username AND email LIKE '$query' ");
        echo '<h1 class="successMessage">You have successfully registered!</h1>';
}
            if($regUsername || $regEmail == $checkIfSame){
            echo '<h1 class="errorMessage">The username or e-mail already exists.</h1>';
        }
?>

将用户名和电子邮件插入数据库后，您正在尝试检查数据库中是否已存在用户名和电子邮件。您应该事先通过选择注册表中提供的用户名和电子邮件，或通过对用户名和电子邮件字段设置唯一键约束来检查。

请使用 mysqli 而不是 mysql，因为它更安全
删除error_reporting（0）
不要使用"喜欢"，因为它可能会有很多结果
MySQL 查询上的语法错误

试试这个只是调试如果有错误，但我认为这有效

    $regUsername    = $_POST['reg-username'];
$regEmail       = $_POST['reg-email'];
$regPassword    = $_POST['reg-password'];
if(isset($regUsername) && isset($regEmail) && isset($regPassword)){
        $mysqli         = mysqli_connect("localhost","root","","supermazad") or die("Error " . mysqli_error($mysqli)); 
        $queryInsert    = "INSERT INTO users (username, email, password) 
                            VALUES 
                          ('$regUsername', '$regEmail', '$regPassword')"; 
        mysqli_query($mysqli, $queryInsert); //this will insert the data from db
        $queryUser  = "SELECT username,email FROM users WHERE username = '$regUsername' AND email = '$regEmail'"; // this will authenticate and uses an exact match
        $result     = $mysqli->query($queryUser);
        $row        = mysqli_fetch_array($result);
        echo '<h1 class="successMessage">You have successfully registered!</h1>';
}
            if($regUsername == $row['username'] && $regEmail == $row['email']){ //this check if email and username are match with database $row['username'] store username from mysql field and $row['email'] do the same
            echo '<h1 class="errorMessage">The username or e-mail already exists.</h1>';
        }

顺便说一下，这对初学者来说是正常的，但请在不久的将来改进您的编码，使其更清晰和有条理

我认为你应该在$selectDB = mysql_select_db('supermazad');之后这样做：

$checkIfSame = mysql_query("SELECT * FROM users WHERE username LIKE '".$regUsername."' OR email LIKE '".$regEmail."' ");
if (mysql_num_rows($checkIfSame ) > 0) {
    echo '<h1 class="errorMessage">The username or e-mail already exists.</h1>';
} else {
    //insert new user here
    $query = mysql_query("INSERT INTO users (username, email, password) VALUES ('$regUsername', '$regEmail', '$regPassword')");
}

另外，您的帖子中有这个：

如果电子邮件或用户名匹配

所以你应该使用 OR ，而不是AND

试试这个：

$checkIfSame = mysql_query("SELECT * FROM users WHERE username LIKE '".$regUsername."' OR email LIKE '".$regEmail."' ");
if (mysql_num_rows($checkIfSame ) > 0) {
    echo '<h1 class="errorMessage">The username or e-mail already exists.</h1>';
} else {
    //insert new user here
    $query = mysql_query("INSERT INTO users (username, email, password) VALUES ('$regUsername', '$regEmail', '$regPassword')");
}