Create a Simple PHP Contact Us Form

<?php
function cleanvars($content) { // Declare the cleanvars function
    $content = htmlspecialchars($content, ENT_QUOTES, 'UTF-8'); // Escape HTML characters
    $content = strip_tags($content); // Strip HTML tags
    $content = addslashes($content); // Add slashes to escape special characters
    return $content; // Return the sanitized content
}
?>

<?php
echo 'Contact Us'; // Display the page title
 
if (isset($_POST['contact'])) { // Check if the form has been submitted
    $name = cleanvars($_POST['name']); // Sanitize the name input
    $email = cleanvars($_POST['email']); // Sanitize the email input
    $subject = cleanvars($_POST['subject']); // Sanitize the subject input
    $message = cleanvars($_POST['message']); // Sanitize the message input
 
    // Validate form inputs
    if (empty($name)) {
        echo 'Please enter your name.';
    } else if (empty($email) || !filter_var($email, FILTER_VALIDATE_EMAIL)) {
        echo 'Please enter a valid email address.';
    } else if (empty($subject)) {
        echo 'Please enter the subject.';
    } else if (empty($message)) {
        echo 'Please enter your message.';
    } else {
        // Send the email
        $to = 'YOUR_EMAIL@example.com'; // Replace with your email
        $headers = 'From: ' . $email;
        if (mail($to, $subject, $message, $headers)) {
            echo 'Mail sent successfully.';
        } else {
            echo 'Failed to send mail. Please try again.';
        }
    }
} else {
    // Display the form
    echo '
    <center>
    <form method="post">
    <table width="80%" border="0">
        <tr>
            <td width="30%"><b>Your Name</b></td>
            <td width="70%"><input type="text" name="name" /></td>
        </tr>
        <tr>
            <td width="30%"><b>Your Email</b></td>
            <td width="70%"><input type="text" name="email" /></td>
        </tr>
        <tr>
            <td width="30%"><b>Subject</b></td>
            <td width="70%"><input type="text" name="subject" /></td>
        </tr>
        <tr>
            <td width="30%"><b>Message</b></td>
            <td width="70%"><textarea name="message"></textarea></td>
        </tr>
        <tr>
            <td width="30%"></td>
            <td width="70%"><input type="submit" name="contact" value="Contact Us" /></td>
        </tr>
    </table>
    </form>
    </center>';
}
?>