javascript - Php 抛出 SQLi 计数错误

Question

<? php

include_once("connection.php");

// email and password sent from form 
$email = $_POST['email'];
$password = $_POST['password'];

// To protect MySQL injection (more detail about MySQL injection)
$email = stripslashes($email);
$password = stripslashes($password);
$email = mysqli_real_escape_string($connection, $_POST['email']);
$password = mysqli_real_escape_string($connection, $_POST['password']);
$sql = "SELECT * FROM users WHERE email='$email' and password='$password'";
$result = mysqli_query($connection, $sql);

// Mysql_num_row is counting table row
$count = mysqli_num_rows($connection, $result);

// If result matched $username and $password, table row must be 1 row
if ($count == 1) {
  session_start();
  $_SESSION['loggedin'] = true;
  $_SESSION['email'] = $email;
}

?>

<div id="openModal" class="modalDialog">
  <div>
    <a href="#close" title="Close" class="close">X</a>


    <form class="pop" method="post" action="login.php">

      <p class="login">LOGIN</p>
      <div class="form-group">
        <div class="left-inner-addon "><i class="fa fa-envelope-o fa-fw"></i>
          <input type="email" name="email" class="form-control" id="email" placeholder="Email" required>
        </div>
      </div>
      <div class="form-group">
        <div class="left-inner-addon"><i class="fa fa-key fa-fw"></i>
          <input type="password" name="password" class="form-control" id="password" placeholder="Password" required>
        </div>
      </div>
      <p>Forgot Password?</p>

      <div class="form-group">
        <button class="btn btn-default" role="button" name="login" id="login">LOGIN</button>
      </div>
    </form>
  </div>
</div>

<? php
$host = 'localhost';
$user = 'root';
$password = '';
$db = 'members';

$connection = mysqli_connect($host, $user, $password, $db);

if ($connection) {
  echo "Connected Successfully";
} else {
  echo "Error connecting: . mysqli_connect_error()";
}

?>

我有index.php、connection.php 和login.php 文件。我已经创建了 register.php 来注册，它工作正常。在login.php中，它连接成功，但在警告中抛出错误:mysqli_num_rows()期望恰好1个参数，2给定另一件事我想弄清楚我如何知道用户是否登录我的网站我的意思是我想知道它是否存储到数据库中或者我不知道，因为我是 SQL 新手并且登录后应该有有效或无效的电子邮件和密码，但不显示。在我的数据库中，我创建了包含 id、用户名、电子邮件、密码列表的表。请以正确且简单的方式提供帮助，不要让我困惑。

Answer 1

mysqli_num_rows() 函数返回结果集中的行数。

它只接受一个参数，例如 $result，这是必需的。 $result 是 mysqli_query()、mysqli_store_result() 或 mysqli_use_result() 返回的结果集标识符。您正在传递 $connection 对象以及导致问题的 $result。

要在数据库中保存 session ，请引用这些帖子

Storing Sessions in a Database

或

Saving PHP's Session data to a database