Question

可能重复：
PHP: “Notice: Undefined variable” and “Notice: Undefined index”

我正在尝试在数据库（MySQL）中注册用户的注册表单。

代码应该注册：

名称
姓
用户名
密码
电子邮件
安全问题
安全答案

代码在保存到表之前，检查用户名或密码是否已经存在，如果他们这样做，则回显错误消息，如果没有，则保存到数据库。

但是，在页面加载时，我遇到了这些错误：

Notice: Undefined index: Name in C:\xampp\htdocs\Task2\registration.php on line 216

Notice: Undefined index: Surname in C:\xampp\htdocs\Task2\registration.php on line 217

Notice: Undefined index: Username in C:\xampp\htdocs\Task2\registration.php on line 219

Notice: Undefined index: Email in C:\xampp\htdocs\Task2\registration.php on line 221

Notice: Undefined index: C_Email in C:\xampp\htdocs\Task2\registration.php on line 222

Notice: Undefined index: password in C:\xampp\htdocs\Task2\registration.php on line 224

Notice: Undefined index: c_password in C:\xampp\htdocs\Task2\registration.php on line 225

Notice: Undefined index: SecQ in C:\xampp\htdocs\Task2\registration.php on line 227

Notice: Undefined index: SecA in C:\xampp\htdocs\Task2\registration.php on line 228

Notice: Undefined variable: mysql_connect in C:\xampp\htdocs\Task2\registration.php on line 231

Fatal error: Function name must be a string in C:\xampp\htdocs\Task2\registration.php on line 231

这是代码：

    <?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
      "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>

  <title>Registration</title>

  <style type="text/css" title="Amaya theme">

body {
    font-size: 12pt;
    font-family: Helvetica, Arial, sans-serif;
    font-weight: normal;
    font-style: normal;
    color: black;
    background-color: white;
    line-height: 1.2em;
    margin-left: 4em;
    margin-right: 2em;
   }

/* paragraphs */
p  {
    padding: 0;
    margin-top: 1em;
    margin-bottom: 1em;
    text-align: left;
   }

/* headings */
h1 {
    font-size: 180%;
    font-weight: bold;
    font-style: normal;
    font-variant: small-caps;
    text-align: left;
    padding: 0;
    margin-top: 1.7em;
    margin-bottom: 1.7em;
   }
h2 {
    font-size: 150%;
    font-weight: bold;
    font-style: normal;
    padding: 0;
    margin-top: 1.5em;
    margin-bottom: 1.1em;
   }
h3 {
    font-size: 130%;
    font-weight: bold;
    font-style: normal;
    padding: 0;
    margin-top: 1.3em;
    margin-bottom: 1.1em;
   }
h4 {
    font-size: 110%;
    font-weight: bold;
    font-style: normal;
    padding: 0;
    margin-top: 1.1em;
    margin-bottom: 1.1em;
   }
h5 {
    font-size: 100%;
    font-weight: bold;
    font-style: italic;
    padding: 0;
    margin-top: 1em;
    margin-bottom: 1em;
   }
h6 {
    font-size: 100%;
    font-weight: normal;
    font-style: italic;
    padding: 0;
    margin-top: 1em;
    margin-bottom: 1em;
   }

/* divisions */
div {
    padding: 0;
    margin-top: 0em;
    margin-bottom: 0em;
   }

/* lists */
ul, ol {
    padding: 0 0 0 3em;
    margin-top: 1em;
    margin-bottom: 1em;
   }
ul ul, ol ol, ul ol, ol ul {
    margin-top: 1em;
    margin-bottom: 1em;
   }
li {
    padding: 0;
    margin-top: 1em;
    margin-bottom: 1em;
    text-align: left;
   }
li p {
    margin-top: 1em;
    margin-bottom: 1em;
   }
dl {
    padding: 0;
    margin-top: 1em;
    margin-bottom: 1em;
    margin-left: 1em;
   }
dl dl {
    margin-top: 0em;
    margin-bottom: 0em;
   }
dt {
    padding: 0;
    font-weight: bold;
    margin-top: .3em;
    margin-bottom: .3em;
   }
dd {
    padding: 0;
    margin-top: .3em;
    margin-left: 3em;
    margin-bottom: .3em;
   }
dl p {
    margin-top: .3em;
    margin-bottom: .3em;
   }

/* inline */
strong {
    font-weight: bold;
   }
em {
    font-style: italic;
   }
code {
    font-family: Courier New, Courier, monospace;
   }
ins {
    background-color: yellow;
    text-decoration: underline;
   }
del {
    text-decoration: line-through;
   }


a[href] {
    color: blue;
    text-decoration: underline;
   }


  </style>
</head>

<body>
<h4><span style="font-family: Arial,Helvetica,sans-serif">Name</span></h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="text"  name='Name'/></p>

<h4 style="font-family: Arial,Helvetica,sans-serif">Surname</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="text" name='Surname'/></p>

<h4 style="font-family: Arial,Helvetica,sans-serif">Username</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="text" name='Username' /></p>
<hr style="font-family: Arial,Helvetica,sans-serif" />

<h4 style="font-family: Arial,Helvetica,sans-serif">Email</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="text" name='Email' /></p>

<h4 style="font-family: Arial,Helvetica,sans-serif">Confirm Email</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="text" name='C_Email' /></p>
<hr style="font-family: Arial,Helvetica,sans-serif" />

<h4 style="font-family: Arial,Helvetica,sans-serif">Password</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="password" name='password' /></p>

<h4 style="font-family: Arial,Helvetica,sans-serif">Confirm Password</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="password" name='c_password'/></p>
<hr style="font-family: Arial,Helvetica,sans-serif" />

<h4 style="font-family: Arial,Helvetica,sans-serif">Security Question</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="password" name='SecQ' /></p>

<h4 style="font-family: Arial,Helvetica,sans-serif">Security Answer</h4>

<p style="font-family: Arial,Helvetica,sans-serif"> <input type="password" name='SecA'/></p>
<hr style="font-family: Arial,Helvetica,sans-serif" />

<hr style="font-family: Arial,Helvetica,sans-serif" />


<p><span
style="font-family: Arial,Helvetica,sans-serif"><button>Submit</button></span></p>

</body>

</html>
<?php
$Name = $_POST['Name'];
$Surname = $_POST['Surname'];

$Username = $_POST['Username'];

$Email = $_POST['Email'];
$C_Email = $_POST['C_Email'];

$Password = $_POST['password'];
$C_Password = $_POST['c_password'];

$SecQ = $_POST['SecQ'];
$SecA = $_POST['SecA'];


$mysql_connect ('localhost', 'admin', 'storefile1234');
mysql_select_db ("storefile");

$check_username = mysql_query("SELECT FROM users WHERE username = '$Username'");
$check_email = mysql_query("SELECT FROM users WHERE email = '$Email'");


if ($Name == null || $Surname== null || $Username == null || $Password == null || $C_Password == null || $Email == null || $C_Email == null || $SecQ == null || $SecA == null ) {

    echo "Missing details. Please enter all fields.";


} else {

    if(mysql_num_rows($check_username) != 0 && mysql_num_rows($check_email) != 0)
            {
            echo "Username/Email already exists";
            }
            if  ($Email == $C_Email && $Password == $C_Password) {

                $query = "INSERT INTO users (Username, Name,Surname, Password, Email, SecQ, SecA) VALUES ('NULL', ".$Username."', ".$Name."', ".$Surname."', ".$Password."', ".$SecQ."', ".$SecA."', ".$Email.')"';

                mysql_query($query) or die ('Error registering.');

                echo "Greetings, ".$Name.", you have been registered. ";

    }  else {

        echo "Error registering your account. Please try again.";
            }

 }


?>

任何帮助都将不胜感激。

谢谢！

Answer 1

在从$_POST中提取值之前，您应该检查它们是否存在。您可以使用isset函数（http://php.net/manual/en/function.isset.php）

Answer 2

您收到错误是因为您尝试阅读尚未设置的帖子变量，只会在表单提交时设置。将您的PHP代码包装在

的底部

if ($_SERVER['REQUEST_METHOD'] === 'POST') { ... }

此外，您的代码适合SQL注入。至少在post vars上使用mysql_real_escape_string，然后在SQL查询中使用它们。 mysql_real_escape_string对于制作网站来说不够好，但是应该在课堂上给你加分。

Answer 3

您是如何加载此页面的？是否在POST上加载任何内容？如果不是，那么$ name = $ _POST ['Name'];分配在POST上没有任何“名称”。

Answer 4

首先，

mysql_connect（）不应该附带$;它不是变量，而是预定义的函数。删除$以正确连接到数据库。

为什么在本文档的顶部有XML标记？这是HTML / PHP - HTML文档类型就足够了。

从第215行开始，更新：

if (isset($_POST)) {
    $Name = $_POST['Name'];
    $Surname = $_POST['Surname'];

    $Username = $_POST['Username'];

    $Email = $_POST['Email'];
    $C_Email = $_POST['C_Email'];

    $Password = $_POST['password'];
    $C_Password = $_POST['c_password'];

    $SecQ = $_POST['SecQ'];
    $SecA = $_POST['SecA'];
}

POST变量来自您的表单，您必须检查它们是否存在，否则PHP会给您一个NOTICE错误。您可以通过放置error_reporting（0）来禁用这些通知;位于文档顶部。为了开发目的，最好将它们保持可见。

您应该只在提交表单的条件下与数据库交互（插入，检查）。如果不这样做，PHP将在没有用户输入的情况下运行所有这些操作。最好使用IF语句，如下所示：

if (isset($_POST['submit']) {
// blah blah
// check if user exists, check if fields are blank
// insert the user if all of this stuff checks out..
} else {
// just display the form
}

令人敬畏的表单教程：http://php.about.com/od/learnphp/ss/php_forms.htm

PHP - 注意：未定义的索引：

4 个答案: