注意：未定义的变量：导致第 42 行的 new_admin.php

Question

我知道我有一个重复的问题，但我已经在 google 上搜索过很多次关于这个的问题，但仍然尝试了很多例子，但我仍然无法弄清楚。我知道我的代码不安全，大家帮我看看我的代码有什么问题。我正在尝试创建注册表单。

代码如下：

<?php
if(isset($_POST['submit'])) {
    global $con;

    $firstname = isset($_POST['first_name']) ? $_POST['first_name'] : '';
    $lastname = isset($_POST['last_name']) ? $_POST['last_name'] : '';
    $email = isset($_POST['email']) ? $_POST['email'] : '';
    $username = isset($_POST['username']) ? $_POST['username'] : '';
    $password = isset($_POST['password']) ? $_POST['password'] : '';
    //$role = isset($_POST['role']) ? $_POST['role'] : '';
    //$status = isset($_POST['status']) ? $_POST['status'] : '';
    $cpassword = isset($_POST['cpassword']) ? $_POST['cpassword'] : '';


    //$login_query=mysqli_query($con, "SELECT * FROM admin where id = $id_session");
    //$count=mysqli_num_rows($login_query);
    //$row=mysqli_fetch_array($login_query);
    //$type=$row['username'];

    if($password != $cpassword) {
        ?>
            <script type="text/javascript">
                alert("Password doesn't match");
            </script>
        <?php
    } else { 
        $query = "INSERT INTO reg_requests (first_name, last_name, email, username, password) VALUES ('{$firstname}', '{$lastname}', '{$email}', '{$username}', '{$password}')";
        $result = mysqli_query($con, $query);
    }

    if($result && mysqli_affected_rows($con) == 1) {
        //mysqli_query($con, "INSERT INTO history (date,action,user) VALUES (NOW(), 'Created Admin: $username', '$type')")or die(mysql_error());
        ?>
        <script type="text/javascript">
            alert("Admin creation success, waiting for Admin's approval!");
            location.href="adLogin.php";
        </script>
        <?php
}  else {
    ?>
        <script type="text/javascript">
            alert("Admin creation failed");
        </script>
    <?php
}
}
?>


<link rel="stylesheet" type="text/css" href="../css/style.css" media="all" />

<body class="align">

<h1 style="color:seashell; margin-bottom:0px; font-size:44px; font-family:Josefin Slab;">JAIL MANAGEMENT SYSTEM</h1>
<h2 style="color:seashell; font-family:Josefin Slab;">Registration</h2>

<div class="grid">

  <form method="POST" class="form login">

    <div class="form__field">
      <label for="login__username"><svg class="icon"><img src="../img/fname.png" width="20" /></svg><span class="hidden">Fname</span></label>
      <input id="login__username" value="" type="text" name="first_name" class="form__input" placeholder="First Name" required/>
    </div>

    <div class="form__field">
      <label for="login__username"><svg class="icon"><img src="../img/fname.png" width="20" /></svg><span class="hidden">Lname</span></label>
      <input id="login__username" value="" type="text" name="last_name" class="form__input" placeholder="Last Name" required/>
    </div>

    <div class="form__field">
      <label for="login__username"><svg class="icon"><img src="../img/email.png" width="20" /></svg><span class="hidden">Email</span></label>
      <input id="login__username" value="" type="email" name="email" class="form__input" placeholder="E-mail" required/>
    </div>

    <div class="form__field">
      <label for="login__username"><svg class="icon"><img src="../img/admin_icon.png" width="20" /></svg><span class="hidden">Username</span></label>
      <input id="login__username" value="" type="text" name="username" class="form__input" placeholder="Username" required/>
    </div>

    <div class="form__field">
      <label for="login__username"><svg class="icon"><img src="../img/password.png" width="20" /></svg><span class="hidden">Password</span></label>
      <input id="login__username" value="" type="password" name="password" class="form__input" placeholder="Password" required/>
    </div>


    <div class="form__field">
      <label for="login__username"><svg class="icon"><img src="../img/password.png" width="20" /></svg><span class="hidden">Cpassword</span></label>
      <input id="login__username" value="" type="password" name="cpassword" class="form__input" placeholder="Confirm Password" required/>
    </div>

    <div class="form__field">
      <input type="submit" name="submit" value="Submit">
    </div>

  </form>

  <p class="text--center"><a href="adLogin.php">Cancel</a></p>

</div>

Answer 1

您的 $result 变量未在条件之前定义。如下更改您的代码。

if($password != $cpassword) {
        $result = FALSE; // If password dosent match define the result as false.
        ?>
            <script type="text/javascript">
                alert("Password doesn't match");
            </script>
        <?php
    } else { 
        $query = "INSERT INTO reg_requests (first_name, last_name, email, username, password) VALUES ('{$firstname}', '{$lastname}', '{$email}', '{$username}', '{$password}')";
        $result = mysqli_query($con, $query);
    }

注意：未定义的变量：导致第 42 行的 new_admin.php

Notice : Undefined variable: result in new_admin.php on line 42

php

mysql

mysqli

registration