PHP Ajax Upload Progress Bar

Answer 1

Introduction

The PHP Doc is very detailed it says

The upload progress will be available in the $_SESSION superglobal when an upload is in progress, and when POSTing a variable of the same name as the session.upload_progress.name INI setting is set to. When PHP detects such POST requests, it will populate an array in the $_SESSION, where the index is a concatenated value of the session.upload_progress.prefix and session.upload_progress.name INI options. The key is typically retrieved by reading these INI settings, i.e.

All the information you require is all ready in the PHP session naming

• start_time
• content_length
• bytes_processed
• File Information ( Supports Multiple )

All you need is to extract this information and display it in your HTML form.

Basic Example

a.html

b.php

session_start();
header('Content-type: application/json');
echo json_encode($_SESSION["upload_progress_upload"]);

Example with PHP Session Upload Progress

Here is a better optimized version from PHP Session Upload Progress

JavaScript

$('#fileupload').bind('fileuploadsend', function (e, data) {
    // This feature is only useful for browsers which rely on the iframe transport:
    if (data.dataType.substr(0, 6) === 'iframe') {
        // Set PHP's session.upload_progress.name value:
        var progressObj = {
            name: 'PHP_SESSION_UPLOAD_PROGRESS',
            value: (new Date()).getTime()  // pseudo unique ID
        };
        data.formData.push(progressObj);
        // Start the progress polling:
        data.context.data('interval', setInterval(function () {
            $.get('progress.php', $.param([progressObj]), function (result) {
                // Trigger a fileupload progress event,
                // using the result as progress data:
                e = document.createEvent('Event');
                e.initEvent('progress', false, true);
                $.extend(e, result);
                $('#fileupload').data('fileupload')._onProgress(e, data);
            }, 'json');
        }, 1000)); // poll every second
    }
}).bind('fileuploadalways', function (e, data) {
    clearInterval(data.context.data('interval'));
});

progress.php

$s = $_SESSION['upload_progress_'.intval($_GET['PHP_SESSION_UPLOAD_PROGRESS'])];
$progress = array(
        'lengthComputable' => true,
        'loaded' => $s['bytes_processed'],
        'total' => $s['content_length']
);
echo json_encode($progress);

Other Examples

• Tracking Upload Progress with PHP and JavaScript
• PHP-5.4-Upload-Progress-Example