Sending status data via JSON response to POST - parse via JavaScript

Question

I have a PHP code for uploading files, which works fine, and as final outcome I have sent JSON response with uploading status which I'm not able to retrieve.

After uploading file (POST) my response looks like:

{"html_content":"<p>File was uploaded<\/p>"}   

PHP uploader code looks like:

if (!is_file($targetFile)) {
    move_uploaded_file($tempFile,$targetFile);
    $html_content="<p>File was uploaded</p>";
}
else {
    $html_content="<p>You have uploaded duplicate.</p>";
    move_uploaded_file($tempFile,$targetFile);  
}

$json_array=array('html_content'=>$html_content);

header('Content-type: text/json');
header('Content-type: application/json');
echo json_encode($json_array);

and JavaScript main code to get message displayed:

this.on("success", function(file,responseText) {
    $.ajax({
        dataType: 'json',
        success: function (response) {

             var htmlElement = document.createElement("div");
             htmlElement.setAttribute("class","success-message");
             var responseText = response.html_content;
             var messageText = document.createTextNode(responseText);
             htmlElement.appendChild(messageText);
             file.previewTemplate.appendChild(htmlElement);

             console.log(response.html_content);
        }
    });
});

When I will unwrap above JS from AJAX part and set variable responseText as a static all works fine.

Also when I will not use AJAX and just output console.log(responseText); I'm getting this in the console:

Object {html_content: "<p>File was uploaded</p>"}

Any clue what I have missed in my case?

Answer 1

You're not sending a request to your PHP server. Specify URL argument.

 $.ajax({url: "your_php_file",
         dataType: 'json',
         success: function (response) {
                   ...
                }
            });

Or even better:

$.getJSON( "your_php_file", function( data ) { ... });

Answer 2

OK, got it solved. JavaScript code looks like

        this.on("success", function(file,responseText) {

            str = JSON.stringify(responseText);
            responseMessage = $.parseJSON(str);

            var htmlElement = document.createElement("div");
            htmlElement.setAttribute("class","success-message");
            htmlElement.innerHTML = responseMessage.html_content;
            file.previewTemplate.appendChild(htmlElement);
        });