所以我正在整理一个表格，并建议我验证表格。我找到了一个教程，但似乎仍然无法让 php 正常运行。
表单的 html：
<div id="FGSform">
<form action="/working/wp-content/themes/NEW/mail.php" method="post" name="contactFGS" id="contactFGS">
<ul>
<li>
<label for="first-name">First Name</label>
<br>
<input type="text" id="firstname" name="firstname" required aria-required="true">
</li>
<br>
<li>
<label for="last-name">Last Name</label><br>
<input type="text" id="lastname" name="lastname" required aria-required="true">
</li>
<br>
<li>
<label for="email">Email</label>
<br>
<input type="email" id="email" name="email" required aria-required="true">
</li>
<br>
<li>
<label for="contact-reason" id="reason" name="reason">Reason for Contact</label>
<select id="reason" name="reason" required>
<option value="."></option>
<option value="Print Services">Print Services</option>
<option value="Design Services">Design Services</option>
<option value="Employment">Employment</option>
<option value="Questions">Questions</option>
<option value="Other">Other</option>
</select>
</li>
<br>
<li>
<label for="comments">Comments</label>
<br>
<textarea name="contactcomments" id="contactcomments" cols="40" rows="10" required></textarea>
</li>
<br>
<li>
<input type="radio" id="newsletter" name="newsletter">
<label for="signmeup">Sign me up for newsletter, updates and other information about FGS</label>
</li>
<br>
<li>
<input type="submit" value="Send" name="submit">
</li>
这是php：
<?php
/*Validate and Sanitaize */
if (isset($_POST['submit'])){
}
if ($_POST['firstname'] != "") {
$_POST['firstname'] = filter_var($_POST['firstname'], FILTER_SANITIZE_STRING);
if ($_POST['firstname'] == "") {
$errors .= 'Please enter a valid name.<br/><br/>';
}
} else {
$errors .= 'Please enter your name.</br>';
}
if ($_POST['lastname'] != "") {
$_POST['lastname'] = filter_var($_POST['lastname'], FILTER_SANITIZE_STRING);
if ($_POST['lastname'] == "") {
$errors .= 'Please enter a valid name.<br/><br/>';
}
} else {
$errors .= 'Please enter your last name.</br>';
}
if ($_POST['emial'] != "") {
$email = filter_var($_POST['email'], FILTER_SANITIZE_EMAIL);
if (!filter_var($email, FILTER_VALITDATE_EMAIL)) {
$errors .="$email is <strong>NOT</strong> a valid email address.<br/<br/>";
}
} else {
$errors .= 'Please enter your email address.<br/>';
}
if (isset($_REQUEST['reason']) && $_REQUEST['reason'] =='.') {
echo 'Please select a reason for contacting.<br/>';
}
if ($_POST['contactcomments'] != "") {
$_POST['contactcomments'] = filter_var($_POST['contactcomments'], FILTER_SANITIZE_STRING);
if ($_POST['contactcomments'] == "") {
$errors .='Please enter a message to send.<br/>';
}
} else {
$errors .='Please enter a message to send.<br/>';
}
/* Email Variables */
$emailSubject = 'Website Mail!';
$webMaster = 'email@here.com';
/* Data Variables */
$firstname = $_POST['firstname'];
$lastname = $_POST['lastname'];
$email = $_POST['email'];
$reason = $_POST['reason'];
$contactcomments = $_POST['contactcomments'];
$newsletter = $_POST['newsletter'];
$body = <<<EOD
<br><hr><br>
Name: $firstname <br>
Last Name: $lastname <br>
Email: $email <br>
Reason: $reason <br>
Comments: $contactcomments <br>
Newsletter = $newsletter <br>
EOD;
$headers = "From: $email\r\n";
$headers .= "Content-type: text/html\r\n";
$success = mail($webMaster, $emailSubject, $body,
$headers);
/* Results rendered as HTML */
$theResults = <<<EOD
<html>
<head>
<title>sent message</title>
<meta http-equiv="refresh" content="3;URL=http://mywebsite.com/working/? page_id=8">
<style type="text/css">
<!--
body {
background-color: #fff;
font-family: Arial, Helvetica, sans-serif;
font-size: 20px;
font-style: normal;
line-height: normal;
font-weight: normal;
color: #555555;
text-decoration: none;
padding-top: 200px;
margin-left: 150px;
width: 800px;
}
-->
</style>
</head>
<div align="center">Thank you! We will contact you back as soon as posible.</div>
</div>
</body>
</html>
EOD;
echo "$theResults";
?>
我遇到的问题是一个人可以提交无效的电子邮件，他们也可以选择无效的选择项。
我将表单的操作连接到 php 文件，但我不确定是否需要让每个表单元素调用 php 文件的特定 if/then 语句。
我是 php 新手，所以这已被证明是一个真正的挑战。
感谢任何提供帮助的人。