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Benton Demeter
Benton Demeter
15,116 Points

How to Create an AJAX/PHP Contact Form

I have used this tutorial http://blog.teamtreehouse.com/create-ajax-contact-form to create a contact form on my website. Every time I hit the submit button it gives me the 400 error code

"Oops! There was a problem with your submission. Please complete the form and try again."

I have looked around and can't find a solution anywhere. Being that I know next to nothing with PHP yet. I would really appreciate a solution. Thanks!


<div id="form-messages"></div>

        <form id="ajax-contact" method="post" action="mailer.php">
            <div class="field">
                <label for="name">Name:</label>
                <input type="text" id="name" name="name" required>

            <div class="field">
                <label for="email">Email:</label>
                <input type="email" id="email" name="email" required>

            <div class="field">
                <label for="message">Message:</label>
                <textarea id="message" name="message" required></textarea>

            <div class="field">
                <button type="submit">Send Message</button>



$(function() {

    // Get the form.
    var form = $('#ajax-contact');

    // Get the messages div.
    var formMessages = $('#form-messages');

    // Set up an event listener for the contact form.
    $(form).submit(function(e) {
        // Stop the browser from submitting the form.

        // Serialize the form data.
        var formData = $(form).serialize();

        // Submit the form using AJAX.
            type: 'POST',
            url: $(form).attr('action'),
            data: formData
        .done(function(response) {
            // Make sure that the formMessages div has the 'success' class.

            // Set the message text.

            // Clear the form.
        .fail(function(data) {
            // Make sure that the formMessages div has the 'error' class.

            // Set the message text.
            if (data.responseText !== '') {
            } else {
                $(formMessages).text('Oops! An error occured and your message could not be sent.');




    // My modifications to mailer script from:
    // http://blog.teamtreehouse.com/create-ajax-contact-form
    // Added input sanitizing to prevent injection

    // Only process POST reqeusts.
    if ($_SERVER["REQUEST_METHOD"] == "POST") {
        // Get the form fields and remove whitespace.
        $name = strip_tags(trim($_POST["name"]));
                $name = str_replace(array("\r","\n"),array(" "," "),$name);
        $email = filter_var(@$_POST[‘email’], FILTER_SANITIZE_EMAIL );
        $message = trim($_POST["message"]);

        // Check that data was sent to the mailer.
        if ( empty($name) OR empty($message) OR !filter_var($email, FILTER_VALIDATE_EMAIL)) {
            // Set a 400 (bad request) response code and exit.
            echo "Oops! There was a problem with your submission. Please complete the form and try again.";

        // Set the recipient email address.
        // FIXME: Update this to your desired email address.
        $recipient = "james3232@gmail.com";

        // Set the email subject.
        $subject = "New contact from $name";

        // Build the email content.
        $email_content = "Name: $name\n";
        $email_content .= "Email: $email\n\n";
        $email_content .= "Message:\n$message\n";

        // Build the email headers.
        $email_headers = "From: $name <$email>";

        // Send the email.
        if (mail($recipient, $subject, $email_content, $email_headers)) {
            // Set a 200 (okay) response code.
            echo "Thank You! Your message has been sent.";
        } else {
            // Set a 500 (internal server error) response code.
            echo "Oops! Something went wrong and we couldn't send your message.";

    } else {
        // Not a POST request, set a 403 (forbidden) response code.
        echo "There was a problem with your submission, please try again.";

opening function and closing brackets of app.js file is not going in code box on this comment like it really is in the file. Also the php opening and closings are normally inside the file. Thanks again!

Hi Benton Demeter, just FYI I edited your question to properly format the code blocks.

1 Answer

I just took a cursory glance over the php and this looks odd to me:

 $email = filter_var(@$_POST[‘email’], FILTER_SANITIZE_EMAIL );
//shouldn't it be 
 $email = filter_var($_POST['email'], FILTER_SANITIZE_EMAIL );

In any event I found this because the 400 Error is thrown if you have an Empty name, Empty Message or the above has an issue.

I did not look over the JS as it is not my area if that does not solve it I can take a longer look at the code but I suspect thats the issue.