jQuery AJAX succeeded, but $_POST is empty

Question

This returns "Ok." alert and array(0) { }. How can I get jQuery image variable?

<script>
    var image = canvas.toDataURL('image/png');
    $.ajax({
        type: 'POST',
        data: image,
        success: function() {
            alert('Ok.');
        }
    });
</script>

<?php
    var_dump($_POST);
?>

Gyrocode.com · Answer 1 · 2015-05-17T20:07:15.807

0

You're posting to the same page via AJAX. On the original page you will still see array(0) { } but the page requested via AJAX will contain correct POST data in the response.

Also the correct code to submit image parameter is shown below.

var image = canvas.toDataURL('image/png');
$.ajax({
    type: 'POST',
    data: { 'image' : image },
    success: function(){
        alert('Ok.');
    }
});

See this JSFiddle for demonstration.

edited May 17 '15 at 20:07

answered May 17 '15 at 19:02

Gyrocode.com

57,606
14
150
185

@wavix, You're seeing `array(0){ }` because you're doing AJAX request which doesn't update the current page. In the response to AJAX request your page produces correct output, which can be verified using debugging tools of your favorite browser. Consider switching to form submission using POST if you want to see the output or adjust your PHP script to handle AJAX POST differently than regular GET. It all depends on what you're trying to do. – Gyrocode.com May 17 '15 at 21:34

score 0 · Answer 2 · edited May 23 '17 at 11:51

0

If you just want to upload an image to PHP Web server, via AJAX, You need to have written your Web server to catch the Image data which you have sent.

I suggest you to follow two links:

Hope this may help you to get resolved your problem!

Cheers!

edited May 23 '17 at 11:51

Community

1
1

answered May 17 '15 at 19:54

Randika Vishman

7,983
3
57
80

I don't want to upload an image. I want to use a jQuery variable in PHP, in the same page. – wavix May 17 '15 at 19:57
If you want to use a jQuery variable in PHP, then you may have sent it to the PHP Serverside! – Randika Vishman May 17 '15 at 19:58
Okay, Try the following link and let me know, if it's correct for you I will update the answer http://stackoverflow.com/a/23583747/1752988 – Randika Vishman May 17 '15 at 19:59
If I use, anywhere, `var_dump ($width)` returns the result in the console. It does not help. – wavix May 17 '15 at 20:16
Width is relevant to that answers particular question, but not to yours! Please try to understand the given answer and try to resolve your problem! – Randika Vishman May 17 '15 at 20:19
On that example I used `var_dump($width)`. – wavix May 17 '15 at 20:23

score -1 · Answer 3 · answered May 17 '15 at 20:56

-1

Try this, it will get the variable at the server side

<script>
$.ajax({
        url: "//php serverside url",
        type: "POST",
        data:  new FormData(this),
        contentType: false,
        cache: false,
        processData:false,
        success: function(data)
        {
        //sucess    
        },
        error: function(){

   }
   });
</script>

answered May 17 '15 at 20:56

Ikelie Cyril

130
7

My `$_POST` is still empty. – wavix May 17 '15 at 21:04
in the serverside it should be something like this `$image = $_FILE['file_field_name']['name']` – Ikelie Cyril May 17 '15 at 21:35
So as to get the image variable, which I think will be the value of the image variable – Ikelie Cyril May 17 '15 at 22:14

jQuery AJAX succeeded, but $_POST is empty

3 Answers3