Undefined index on ajax post request

Question

This might seem like a duplicate question, but it isn't. I have searched google but my bug remains.

The issue is that the php script can not set $_POST array to the value being passed by the ajax post request. I have a form that,when submitted,displays another form in the same divs as the first form. The second form contains a submit button, as well as a button which sends ajax post request but it's value is not being set by php. The code is as follows:

html code: it is to pick out value of the span.

<i>Current Balance: <span id="bal_val"><?php echo $b; ?></span></i>
<div id="bal" style='color:green;'>

Ajax code: here, edit button is a button (of the first form) which enables the display of the second form. The second form contains the balbutton input,which sends ajax request.

 $('#edit').click(function(event){  
          event.preventDefault();
$('#bal').html('<button class="btn1 btn-1 btn-1b" id="balbutton" name="balbutton">Add 1000 Rs.</button>');
});

$('#balbutton').click(function(event){
              event.preventDefault();

              var bal = document.getElementById('bal_val').innerHTML;
              var balance = parseInt(bal);
             var dataString = {balance};

               $.ajax({
                                    type: "POST",
                                    url: "admin.php/",
                                    data: dataString,
                                    contentType: 'application/x-www-form-urlencoded',
                                    cache: false,
                                    dataType: 'text',
                                    success: function(result){
                                    var data="";
                                    console.log(result);
                                    $('#bal').html('We will add 1000rs to your account soon');
                                    },
                                    error: function(error){console.log(error);}
                            });  

      });

php code:

<?php 

$bal=$_POST['balance'];

$bal=intval($bal);
echo $bal;

echo '<pre>';
echo print_r($_POST);
echo '</pre><br>';

echo '<pre>';
echo var_dump($_POST);
echo '</pre>';
?>

Also, I have tried the solutions of:

Undefined index: Error in ajax POST and/or php script?

Snapshot of the ajax post request and PHP error

`var dataString = {balance};` Should be `var dataString = {balance:balance};` — Think Different, Jul 19 '16 at 10:09
@vp_arth ES2015/ES6 is not yet natively supported in Firefox. — Praveen Kumar Purushothaman, Jul 19 '16 at 10:19

score 1 · Accepted Answer · answered Jul 19 '16 at 10:09

1

In this part, you are not giving a valid syntax:

var dataString = {balance};

Change the above to:

var dataString = {balance: balance};

answered Jul 19 '16 at 10:09

Praveen Kumar Purushothaman

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yes, i tried that. It didn't work. I also mentioned a link which mentioned the same solution. Thanks anyway! :) – Fabulous Jul 19 '16 at 10:10
@simrandhamija Can you please try doing the same with Chrome, and checking the Network tab, what's going on? A screenshot will be awesome. – Praveen Kumar Purushothaman Jul 19 '16 at 10:11
I added the snap! unfortunately it is on firefox, hope you don't mind. Also i highlighted the relevant post request. – Fabulous Jul 19 '16 at 10:16
@simrandhamija Thanks. Can you also include the **form data** part in it? Sorry that was the main thing I was going behind... – Praveen Kumar Purushothaman Jul 19 '16 at 10:16
@simrandhamija Do you really require this line? `contentType: 'application/x-www-form-urlencoded',` – Praveen Kumar Purushothaman Jul 19 '16 at 10:19
@simrandhamija **Best Quick Fix:** Try using short hand. Replace your `$.ajax({ /* */});` with this: `$.post("admin.php", function (res) { $('#bal').html('We will add 1000rs to your account soon'); });` and tell me if that works. – Praveen Kumar Purushothaman Jul 19 '16 at 10:22
The data i intend to send is not enclosed in a form. the button picks up the inner html of "balance" div, typecasts it to Integer, and posts it to admin. However, the first form is enclosed in
tag. When the first form's submit button is clicked, a second form replaces the first. Should i post that code too int the question? I have checked that portion, i doubt if it affects the issue. – Fabulous Jul 19 '16 at 10:22
@simrandhamija Check my last comment please. That should work. If not I am giving a 1000 ₹ right away! `:)` – Praveen Kumar Purushothaman Jul 19 '16 at 10:23
Trying your best quick fix! thanks for that :). Will comment with the results – Fabulous Jul 19 '16 at 10:23
@PraveenKumar - I think you forgot to add the data in the `$.post()`... – ImClarky Jul 19 '16 at 10:30
@ImClarky The response is not at all considered in the post function... – Praveen Kumar Purushothaman Jul 19 '16 at 10:30
@ImClarky I mean, it doesn't depend on the `res` or `data` or whatever. – Praveen Kumar Purushothaman Jul 19 '16 at 10:32
@simrandhamija Do you have any element with `id="bal"` in your HTML? Can you kindly check, please? – Praveen Kumar Purushothaman Jul 19 '16 at 10:33
yes, a span element. In my post above it is the first line of code. Any idea about the issue! stuck for 2 days now – Fabulous Jul 19 '16 at 10:50
@simrandhamija I could see only the element with `bal_val`, is that a typo? Did you mean to put `$("#bal_val")` instead? – Praveen Kumar Purushothaman Jul 19 '16 at 10:50
sorry, i do have a "bal" div , added it to my post above. I use it to display messages – Fabulous Jul 19 '16 at 10:59
@simrandhamija Yup checked it. Any errors in Console? Come to chat. – Praveen Kumar Purushothaman Jul 19 '16 at 11:00

Undefined index on ajax post request

1 Answers1