我有以下错误：
注意：未定义的索引：在第6行的C：\ wamp \ www \ registration \ register.php中提交
似乎无法解决什么错误???这是代码::
<?php
//Create registration form (register.php)
include "../includes/db_connect.php";
if(!$_POST['submit']) ///Line 6
{
?>
<html>
<head><link rel="stylesheet" href="style.css"></head>
<div class="divider">
<strong>Register</strong>
<form method="post" action="register.php">
<div class="formElm">
<label for="first">First Name</label>
<input id="first" type="text" name="first">
</div>
<div class="formElm">
<label for="last">Last Name</label>
<input id="last" type="text" name="last">
</div>
<div class="formElm">
<label for="username">Desired Username</label>
<input id="username" type="text" name="username">
</div>
<div class="formElm">
<label for="password">Password</label>
<input id="password" type="password" name="password">
</div>
<div class="formElm">
<label for="pass_conf">Confirm Password</label>
<input id="pass_conf" type="password" name="pass_conf">
</div>
<div class="formElm">
<label for="email">Email</label>
<input id="email" type="text" name="email">
</div>
<div class="formElm">
<label for="about">About</label>
<textarea id="about" cols="30" rows="5" name="about">Tell us about yourself</textarea>
</div>
<input type="submit" name="submit" value="Register">
</form>
or <a href="index.php">Login</a>
</div>
</html>
<?php
}
else
{
$first = protect($_POST['first']);
$last = protect($_POST['last']);
$username = protect($_POST['username']);
$password = protect($_POST['password']);
$pass_conf = protect($_POST['pass_conf']);
$email = protect($_POST['email']);
$about = protect($_POST['about']);
$errors = array();
$regex = "/^[a-z0-9]+([_\.-][a-z0-9]+)*@([a-z0-9]+([.-][a-z0-9]+)*)+\.[a-z]{2,}$/i";
if(!preg_match($regex, $email))
{
$errors[] = "E-mail is not in name@domain format!";
}
if(!$first || !$last || !$username || !$password || !$pass_conf || !$email || !$about)
{
$errors[] = "You did not fill out the required fields";
}
$sql = "SELECT * FROM `users` WHERE `username`='{$username}'";
$query = mysql_query($sql) or die(mysql_error());
if(mysql_num_rows($query) == 1)
{
$errors[] = "Username already taken, please try another";
}
if(count($errors) > 0)
{
echo "The following errors occured with your registration";
echo "<font color=\"red\">";
foreach($errors AS $error)
{
echo "<p>" . $error . "\n";
}
echo "</font>";
echo "<a href=\"javascript:history.go(-1)\">Try again</a>";
//we use javascript to go back rather than reloading the page
// so the user doesn't have to type in all that info again.
}
else
{
$sql = "INSERT into `users`(`first`,`last`,`username`,`password`,`email`,`about`)
VALUES ('$first','$last','$username','".md5($password)."','$email','$about');";
$query = mysql_query($sql) or die(mysql_error());
echo "Thank You for registering {$first}! Your username is {$username}";
echo "<a href=\"index.php\"> Click here </a> to Login";
}
}
?>
4 回答
要摆脱这个错误，它应该是：
但是，您的代码已经可以了 .
你得到的不是错误，而是一个警告，这是由严格的警告引起的 . PHP是一种动态语言，通常不需要定义变量和数组键，大多数文档和代码都会跳过这一部分 . 因此，您应该考虑关闭此功能，因为它会使代码混乱并且几乎没有其他好处 . 或者，切换到静态编译的语言（比如asp.net），它将真正受益于已定义的变量和静态类型 .
如果根本没有POST参数或者没有名为
submit的参数，那么您正在尝试访问不存在的数组索引，因此警告 . 您可以简单地测试_POST数组中是否存在这样的索引/元素 .它没有't check the value (like you original script, which tests if the value of _POST[' submit']等于false，请参见type juggling），但在这种情况下，仅仅存在索引/元素就足够了 .
见http://docs.php.net/isset
首次加载页面时，$ _POST不存在 . 将支票更改为：
因为您还没有发布任何内容，所以$ _POST数组中没有“submit”键 . 这就是导致警告的原因 .
对于那些发布使用if（isset（$ _ POST ['submit']）），你显然没有阅读他的代码 . 他放的是没有提交写HTML表单其他使用字段（向后扶正我！）
如果他想保持结构原样，它应该是