Why am I seeing a value of "undefined" on screen when I submit form in jQuery Mobile?

php javascript jquery-mobile

14,481

Solution 1

I'm not sure why you're seeing undefined, but I noticed you are not preventing the default submit action. so your page will still submit rather than executing JS.

You'll need to do a couple things:

Prevent the default action (ie the submission)
Serialize your form data and submit it via ajax.

So in code it would look something like this:

$(document).ready(function() { 
    //Cache DOM reference
    var form = $("#contactus");

    form.submit(function(event) {
        //Prevent the form from regular (non-js) submission
        event.preventDefault();

        //Serialize your data, using jQuery to make it easer
        var data = form.serialize();

        //Submit via ajax
        $.post(
          form.attr('action'),
          data,
          function(response) {
            //You should modify your PHP to return a success or error code, then
            //handle appropriately here - eg if (response === 'success") {...
          }    
        );

     });

});

Solution 2

The reason you get an undefined value is because you post to a non-valid jQuery mobile page. So make sure the server returns a valid jquery mobile HTML page.

Create your jquery mobile form
Set the attribute action="/mobile.html" and method="post" (or get)
Then make sure the page mobile.html (or whatever you want to call it) returns a valid jQuery mobile HTML page.

If you don't know what a valid jquery mobile HTML page is, check the jquery mobile website.

14,481

Author by

jini

Updated on July 13, 2022

Comments

jini almost 2 years

This is my contactus.html page. I am submitting to a php page on the server that is to take the information and send email alongw ith saying thank you. When I do submitthe form, all I see is "undefined" on screen even though I am able to get the email.

<!DOCTYPE html> 
<html> 
    <head> 
    <title>Contact Us</title> 
    <link rel="stylesheet" href="css/latestjquerymobile.css" />
    <link rel="stylesheet" type="text/css" href="css/jquery.mobile.simpledialog.min.css" />

    <script type="text/javascript" src="js/jquery-1.6.1.min.js"></script>
    <script type="text/javascript" src="js/latestjquerymobile.js"></script>
    <script type="text/javascript" src="js/jquery.mobile.simpledialog.min.js"></script>


    <script type="text/javascript">
    $(document).ready(function() { 

                     $("#contactus").submit(function(event) {

                     alert("page submitted");


 })

});
</script>
</head> 
<body> 

<div data-role="page" data-theme="e" id="contactus">

    <div data-role="header" data-position="fixed">
        <h1>Contact Us</h1>
        <a href="home.html" data-icon="back" class="ui-btn-left" data-ajax="false">Back</a>
        <a href="home.html" data-icon="home" class="ui-btn-right" data-ajax="false">Home</a>
    </div><!-- /header -->

    <div data-role="content">   

    <div align="center">





    <form action="http://testsite.com/contactus.php" name="contactus" id="contactus" method="post">


    <fieldset>



        <div data-role="fieldcontain">

        <label for="name"> Name:</label>    
        <input id="name" name="name" type="text" />

        <label for="email">Email:</label>       
        <input id="email" name="email" type="text" />


        <label for="contact">Contact:</label>   
        <input id="contact" name="contact" type="text" />


        <label for="message">Message:</label>       
        <textarea rows="4" cols="50" id="message" name="message"></textarea>

        <br />
        <button type="submit" name="submit" value="submit-value">Send</button>


        </fieldset>
    </div>
    </form>




     <div><br><br>


      <a href="http://www.facebook.com/Apsession"><img src="images/facebook.png" border="0" /></a>

    <a href="http://twitter.com/ApsessionMobile"><img src="images/twitter.png" border="0" /></a>


     </div>




    </div>

    </div><!-- /content -->

</div><!-- /page -->

</body>
</html>

This is the code for contactus.php on server

<?php 
$ToEmail = '[email protected]'; 
$EmailSubject = 'Contact Form Submission from testsite.com'; 
$mailheader = "From: ".$_POST["email"]."\r\n"; 
$mailheader .= "Reply-To: ".$_POST["email"]."\r\n"; 
$mailheader .= "Content-type: text/html; charset=iso-8859-1\r\n"; 
$MESSAGE_BODY = "Name: ".$_POST["name"]."<br>"; 
$MESSAGE_BODY .= "Email: ".$_POST["email"]."<br>"; 
$MESSAGE_BODY .= "Contact: ".$_POST["contact"]."<br>";
$MESSAGE_BODY .= "Message: ".$_POST["message"]."<br>"; 
mail($ToEmail, $EmailSubject, $MESSAGE_BODY, $mailheader) or die ("Failure"); 
?>
<html>
<body>

THANK YOU

</body>
</html>

jini over 12 years

Philip, thanks for the great suggesstion however jQuery Mobile prevents any ajax submissions once you get the "#" in the URL since this page was injected into the DOM. I wish i could do the above.
Philip Schweiger over 12 years

That's too bad - not sure how you will be able to reliably run any JS after submission, then, as it'll always be a race condition between your action page loading and the JS executing.