除了$_POST，$fname和$mname之外，我为每个$lname项都收到此错误。我不明白为什么。我已经搜索了一个解决方案，并且isset的建议是最常见的，但我已经尝试了几种不同的形式，它仍然不适合我。
注意：未定义的索引：第13行的C：\ xampp \ htdocs \ php \ signin.php中的邮政编码
注意：未定义的索引：第15行的C：\ xampp \ htdocs \ php \ signin.php中的家庭电话
注意：未定义的索引：第16行的C：\ xampp \ htdocs \ php \ signin.php中的mobphone
signin.php
<?php
if(isset($_POST['submit'])) {
$fname=$_POST['firstname'];
$mname=$_POST['middlename'];
$lname=$_POST['lastname'];
$dob=$_POST['dateofbirth'];
$address=$_POST['address'];
$city=$_POST['city'];
$state=$_POST['state'];
$country=$_POST['country'];
$postcode=$_POST['postcode'];
$email=$_POST['email'];
$homephone=$_POST['homephone'];
$mobphone=$_POST['mobphone'];
$preferred=$_POST['preferred'];
include_once("includes/link.php");
$sql=("INSERT INTO `member` VALUES ('$fname', '$mname', '$lname', '$dob', '$address', '$city', '$state', '$country', '$postcode', '$email', '$homephone', '$mobphone', 'preferred')");
mysqli_query($link, $sql);
mysqli_close($link);
}
?>
link.php
<?php
$hostname = "localhost";
$user = "root";
$password = "********";
$link = mysqli_connect($hostname, $user , $password);
if (!$link){
echo "server is being lame";
exit;
};
mysqli_select_db($link, "cp2cwonrlvDB3");
if (!mysqli_select_db($link, "cp2cwonrlvDB3")){
echo "Could not connect brudda";
};
?>
表格html：
<html>
<head>
<title>Example form</title>
<style type="text/css">
label
{
width: 100px;
float: left;
text-align: right;
margin-right: 0.5em;
display: block
}
.reset {
margin-left:50px;
}
h3 {
margin-left:15px;
}
</style>
<script>
<?php
include 'includes/connection.php'
?>
</script>
</head>
<body>
<div class="container">
<h2>Sign up to CWON</h2>
<form method="POST" action="signin.php" novalidate>
<label for="fisrtname">First Name:</label>
<input type="text" name="firstname" required placeholder="Enter your first name" maxlength="25"><br />
<label for="middlename">Middle Name:</label>
<input type="text" name="middlename" placeholder="Enter your middle name" maxlength="25"><br />
<label for="lastname">Last Name:</label>
<input type="text" name="lastname" required placeholder="Enter your last name" maxlength="25"><br />
<label for="dateofbirth">Date of Birth:</label>
<input type="date" name="dateofbirth" required maxlength="25"><br />
<label for="address">Address:</label>
<input type="text" name="address" required maxlength="100" placeholder="Enter your home address"><br />
<label for="city">City:</label>
<input type="text" name="city" required maxlength="100" placeholder="Enter your city"><br />
<label for="state">State:</label>
<select name="state">
<option value="NSW">NSW</option>
<option value="QLD">QLD</option>
<option value="VIC">VIC</option>
<option value="SA">SA</option>
<option value="WA">WA</option>
<option value="NT">NT</option>
<option value="TAS">TAS</option>
</select> <br />
<label for="country">Country:</label>
<input type="text" name="country" required maxlength="100" placeholder="Enter your country"><br />
<h3>Preferred contact:</h3>
<label for="preferred">Home Phone:</label>
<input type="radio" name="preferred" value="Home Phone"><br /><br />
<label for="preferred">Mobile Phone:</label>
<input type="radio" name="preferred" value="Mobile Phone"><br /><br />
<label for="preferred">Email:</label>
<input type="radio" name="preferred" value="Email"><br /><br />
<label for="homenumber">Home Number:</label>
<input type="text" name="homenumber" placeholder="Enter your home number"><br />
<label for="mobnumber">Mobile Number:</label>
<input type="text" name="mobnumber" placeholder="Enter your mobile number"><br />
<label for="email">Email Address:</label>
<input type="email" name="email" required maxlength="100" placeholder="Enter your email address"><br />
<label for="postcode">Postcode:</label>
<input type="number" name="postcode" required min="1000" max="9999" placeholder="4-digit"><br />
<label for="occupation">Occupation:</label>
<input type="text" name="occupation" maxlength="50" placeholder="Enter your occupation"><br />
<label for="hobbies">Hobbies:</label>
<input type="text" name="hobbies" maxlength="200" placeholder="separate with commas"><br />
<label for="interest">Interests:</label>
<select name="interest">
<option value="Fund Raisers">Fund Raisers</option>
<option value="Domestic Volunteering">Domestic Volunteering</option>
<option value="Foreign Volunteering">Foreign Volunteering</option>
<option value="All of the above">All of the above</option>
</select> <br /><br />
<label for="terms">Terms and Conditions</label>
<input type="checkbox" name="terms"><br /><br /><br />
<label for="newsletter">Sign up for the CWON newsletter</label>
<input type="checkbox" name="newsletter"><br /><br /><br /><br />
<input type="reset" name="reset" value="Reset" class="reset" onclick="set_focus()" />
<input type="submit" name="submit" value="Submit" class="submit">
</form>
</div>
答案 0 :(得分：4)
看到$数组中有$_POST。全部删除它们。
$dob=$_POST['$dateofbirth'];
^------------------ That (Remove them all)
编辑：
您需要更改邮政编码的名称，因为它反映了手机。
<label for="postcode">Postcode:</label>
<input type="number" name="postcode" required min="1000" max="9999" placeholder="4-digit"><br />
现在将它们改为......
$homephone=$_POST['homenumber']; //<--- Should be homenumber.`
$mobphone =$_POST['mobnumber'];
$postcode =$_POST['postcode'];
答案 1 :(得分：2)
在尝试访问参数之前，您需要检查并确保有值。这将确保在您尝试使用它们之前设置它们。这可以使用isset()函数完成。例如：
// check values exist before using them
if(isset($_POST['$dateofbirth'])){
$dob=$_POST['$dateofbirth'];
}
此外，您的SQL易受注入攻击。在查询中使用它们之前，您确实应该清理它们的参数。 MySQLi建议使用参数化查询或PDO查询。
请注意最终错误如何不包含$，因此删除完全无法解决问题。
答案 2 :(得分：1)
变化：
$dob=$_POST['$dateofbirth'];
要：
$dob=$_POST['dateofbirth'];
所有人都一样。
答案 3 :(得分：0)
您没有姓名＆＃39; homephone＆＃39;和＆＃39; mobphone＆＃39;，只是＆＃39; homenumber＆＃39;和＆＃39; mobnumber＆＃39;
$homephone=$_POST['homenumber'];
$mobphone=$_POST['mobnumber'];