所以我实际上对 MySQL 和 MySQLi 之间的区别了解不多，我会在工作的时候慢慢了解它...我正在尝试在这个新网站上使用我的旧 SQL PHP 注册表没有任何运气，我要么得到 "mysqli_query() expects at least 2 parameters, 1 given" 或空白页，要么返回站点错误，例如 "Desired Username is a required字段。请在下方输入。” 何时填写该字段？如果有人能看一看，我将不胜感激!谢谢。

注册.php -

 <?php
if (isset($_GET['signuperror'])) {
    $signuperror = $_GET['signuperror'];
} else {//if there is no choice, display series 1
    $signuperror = 1; 
}

switch($signuperror) {

    case 1:
        echo '';
    break;

    case 2:
       echo "<div class='alert alert-danger'><strong>First Name is a required field. Please enter it below.</strong></span></div> ";
    break;

    case 3:
        echo "<div class='alert alert-danger'><strong>Last Name is a required field. Please enter it below.</strong></span></div> ";
    break;

    case 4:
        echo "<div class='alert alert-danger'><strong>Email Address is a required field. Please enter it below.</strong></span></div> ";
    break;

    case 5:
        echo "<div class='alert alert-danger'><strong>Desired Username is a required field. Please enter it below.</strong></span></div> ";
    break;

    case 6:
        echo "<div class='alert alert-danger'><strong>Your passwords do NOT match, please check your passwords.</strong></span></div> ";
    break;

    case 7:
        echo "<div class='alert alert-danger'><strong>Your email address has already been used by another user. Please use a different Email address.</strong></span></div> ";
    break;

    case 8:
        echo "<div class='alert alert-danger'><strong>The username you have selected has already been used by another user. Please choose a different Username.</strong></span></div> ";
    break;

    case 9:
        echo "<div class='alert alert-danger'><strong>There has been an error creating your account. Please contact the admin.</strong></span></div> ";
    break;

    default:
    break;
}


?> 


              <form name="register" id="register" action="registercode.php" method="POST"> 
                 <div class="register-top-grid">
                    <h3>PERSONAL INFORMATION</h3>
                     <div class="wow fadeInLeft" data-wow-delay="0.4s">
                        <span><b>First Name</b><label>*</label></span>
                        <input type="text" value="" data-msg-required="Please enter your first name." maxlength="100" name="first_name" id="first_name" required> 
                     </div>
                     <div class="wow fadeInRight" data-wow-delay="0.4s">
                        <span><b>Last Name</b><label>*</label></span>
                        <input type="text" value="" data-msg-required="Please enter your last name." maxlength="100" name="last_name" id="last_name" required> 
                     </div>
                     <div class="wow fadeInRight" data-wow-delay="0.4s">
                         <span><b>Email Address</b><label>*</label></span>
                         <input type="email" value="" data-msg-required="Please enter your email address." data-msg-email="Please enter a valid email address." size="68" name="email_address" id="email" required> 
                     </div>
                     <div class="clearfix"> </div>
                       <a class="news-letter" href="#">
                         <label class="checkbox"><input type="checkbox" name="checkbox" checked=""><i> </i>Sign Up for Newsletter</label>
                       </a>
                     </div>
                     <div class="register-bottom-grid">
                            <h3>LOGIN INFORMATION</h3>
                            <div class="wow fadeInLeft" data-wow-delay="0.4s">
                        <span><b>Username</b><label>*</label></span>
                        <input type="text" value="" data-msg-required="Please enter a valid username." maxlength="100" name="username" id="username" required> 
                     </div><div class="clearfix"> </div><div class="clearfix"> </div><div class="clearfix"> </div><div class="clearfix"> </div>
                             <div class="wow fadeInLeft" data-wow-delay="0.4s">
                                <span><b>Password</b><label>*</label></span>
                                <input type="password" value="" name="password" id="password" required>
                             </div>
                             <div class="wow fadeInRight" data-wow-delay="0.4s">
                                <span><b>Confirm Password</b><label>*</label></span>
                                <input type="password" value="" name="passwordcheck" id="passwordcheck"  required>
                             </div>
                     </div>

                <div class="clearfix"> </div>
                <div class="register-but">

                       <input type="submit" value="REGISTER" class="btn btn-info"> | Already a member? <a href="signin.php"><b>Login</b></a>
                       <div class="clearfix"> </div>
                   </form>
                </div>
           </div>
         </div>
    </div>
<!-- registration -->

注册码.php -

    <?

include 'core/init.php';

// Define post fields into simple variables
$first_name = mysqli_real_escape_string($_POST['first_name']);
$last_name = mysqli_real_escape_string($_POST['last_name']);
$email_address = mysqli_real_escape_string($_POST['email_address']);
$username = mysqli_real_escape_string($_POST['username']);
$password = $_POST['password'];
$passwordcheck = $_POST['passwordcheck'];

/* Let's strip some slashes in case the user entered
any escaped characters. */

$first_name = stripslashes($first_name);
$last_name = stripslashes($last_name);
$email_address = stripslashes($email_address);
$username = stripslashes($username);


/* Do some error checking on the form posted fields */

if((!$first_name) || (!$last_name) || (!$email_address) || (!$username) || (!$password) || (!$passwordcheck)){
    if(!$first_name){
        header('Location: register.php?signuperror=2');
    }
    if(!$last_name){
        header('Location: register.php?signuperror=3');
    }
    if(!$email_address){
        header('Location: register.php?signuperror=4');
    }
    if(!$username){
        header('Location: register.php?signuperror=5');
    }
    if ($password !== $passwordcheck){
        header('Location: register.php?signuperror=6');
    }

    include "register.php"; // Show the form again!
    /* End the error checking and if everything is ok, we'll move on to
     creating the user account */
    exit(); // if the error checking has failed, we'll exit the script!
}

/* Let's do some checking and ensure that the user's email address or username
 does not exist in the database */

 $sql_email_check = mysqli_query($conn, "SELECT email_address FROM users WHERE email_address='$email_address'");
 $sql_username_check = mysqli_query($conn, "SELECT username FROM users WHERE username='$username'");

 $email_check = mysqli_num_rows($sql_email_check);
 $username_check = mysqli_num_rows($sql_username_check);

 if(($email_check > 0) || ($username_check > 0)){
    if($email_check > 0){
        header('Location: register.php?signuperror=7');
        unset($email_address);
    }
    if($username_check > 0){
        header('Location: register.php?signuperror=8');
        unset($username);
    }
    include 'register.php'; // Show the form again!
    exit();  // exit the script so that we do not create this account!
 }

/* Everything has passed both error checks that we have done.
It's time to create the account! */

$db_password = md5($password);

// Enter info into the Database.
$info2 = htmlspecialchars($info);
$sql = mysqli_query($conn, "INSERT INTO users (email_address, username, first_name, last_name, password, reg_date, last_login, activated, admin)
        VALUES('$email_address', '$username', '$first_name', '$last_name', '$db_password', now(), now(), '0', '0')") or die (mysqli_error());

if(!$sql){
    header('Location: register.php?signuperror=9');
} else {
    $userid = mysqli_insert_id();
    // Let's mail the user!
    $subject = "Fundfeeder Accounts";
    $message = "Dear $first_name $last_name,
    Thank you for registering at Fundfeeder, http://www.fundfeeder.co.uk/

    You are one step away from logging in and accessing your account.

    To activate your membership, please click here: http://www.fundfeeder.co.uk/activate.php?id=$userid&code=$db_password

    Once you activate your memebership, you will be able to login with the information you provided.

    Thanks!
    FundFeeder Admin Team.

    This is an automated response, please do not reply!";

    mail($email_address, $subject, $message, "From: FundFeeder Accounts<admin@fundfeeder.co.uk>\nX-Mailer: PHP/" . phpversion());
    ////// MAIL ADMIN
    $subject2 = "FundFeeder New User!";
    $message2 = "Dear Admin,
    This is a message to alert you that a new user has signed up to FundFeeder.

    You can view all details of the new member and all other members direct from the admin control panel at http://fundfeeder.co.uk/admin.php

    Here are the details of the new registered user:
    Username: $username
    Email Address: $email_address

    Thanks!
    FundFeeder Accounts.

    This is an automated response, please do not reply!";

    mail('aidan6141@hotmail.co.uk', $subject2, $message2, "From: FundFeeder Accounts<admin@fundfeeder.co.uk>\nX-Mailer: PHP/" . phpversion());
    header('Location: signin.php?loginerror=6');
include 'signin.php';
}

?>

core/init.php(数据库连接)-

<?php
$conn = mysqli_connect("mysql.hostinger.co.uk","u479096627_admin","password", "u479096627_ctrl");
//Evaluate the connection
if (mysqli_connect_errno()) {
    echo mysqli_connect_error();
    exit();
}
?>

最佳答案

您需要将数据库连接定义为所有 msqli_connect 语句的参数。

示例在这里:

    <?php
    $servername = "localhost";
    $username = "username";
   $password = "password";
   $db ="database";

 // Create connection
  $conn = new mysqli($servername, $username, $password, $db);

   // Check connection
  if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
} 
 ?>

现在将查询传递给 msqli_query 时:

$query = "your-SQL-query";
$run = msqli_query($conn,$query);
if(!$run){
 //handle the error here if query fails
  }

要检查任何已存在的行，您需要传递以下内容
在本示例中，它将是:

      $row_check = mysqli_num_rows($run);

希望您现在了解如何使用 msqli* 函数。

关于php - 更新到 SQLi 时 MySQL 注册不起作用？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/29988994/