Multifile uploader

HTML

<!DOCTYPE html>
<html>

	<head>
		<meta charset="utf-8"/>
		<title>File Uploader</title>

		<!-- Google web fonts -->
		<link href="http://fonts.googleapis.com/css?family=PT+Sans+Narrow:400,700" rel='stylesheet' />

		<!-- The main CSS file -->
		<link href="assets/css/style.css" rel="stylesheet" />
	</head>

	<body>

		<form id="upload" method="post" action="upload.php" enctype="multipart/form-data">
			<div id="drop">
				Drop Here

				<a>Browse</a>
				<input type="file" name="upl[]" multiple />
			</div>

			<ul>
				<!-- The file uploads will be shown here -->
			</ul>

		</form>

		<!-- JavaScript Includes -->
		<script src="assets/js/jquery-1.11.3.min.js"></script>
		<script src="assets/js/jquery.knob.js"></script>

		<!-- jQuery File Upload Dependencies -->
		<script src="assets/js/jquery.ui.widget.js"></script>
		<script src="assets/js/jquery.iframe-transport.js"></script>
		<script src="assets/js/jquery.fileupload.js"></script>

		<!-- Our main JS file -->
		<script src="assets/js/script.js"></script>


	</body>
</html>

script.js

$(function(){

    var ul = $('#upload ul');
	var myfiles = [];
    $('#drop a').click(function(){
        // Simulate a click on the file input button
        // to show the file browser dialog
        $(this).parent().find('input').click();
    });

    // Initialize the jQuery File Upload plugin
    $('#upload').fileupload({

        // This element will accept file drag/drop uploading
        dropZone: $('#drop'),

        // This function is called when a file is added to the queue;
        // either via the browse button, or via drag/drop:
        add: function (e, data) {

            var tpl = $('<li class="working"><input type="text" value="0" data-width="48" data-height="48"'+
                ' data-fgColor="#0788a5" data-readOnly="1" data-bgColor="#3e4043" /><p></p><span></span></li>');

            // Append the file name and file size
            tpl.find('p').text(data.files[0].name)
                         .append('<i>' + formatFileSize(data.files[0].size) + '</i>');

            // Add the HTML to the UL element
            data.context = tpl.appendTo(ul);

            // Initialize the knob plugin
            tpl.find('input').knob();

            // Listen for clicks on the cancel icon
            tpl.find('span').click(function(){

                if(tpl.hasClass('working')){
                    jqXHR.abort();
                }

                tpl.fadeOut(function(){
                    tpl.remove();
                });

            });

            // Automatically upload the file once it is added to the queue
            var jqXHR = data.submit();
        },

        progress: function(e, data){

            // Calculate the completion percentage of the upload
            var progress = parseInt(data.loaded / data.total * 100, 10);

            // Update the hidden input field and trigger a change
            // so that the jQuery knob plugin knows to update the dial
            data.context.find('input').val(progress).change();

            if(progress == 100){
                data.context.removeClass('working');
            }
        },

        fail:function(e, data){
            // Something has gone wrong!
            data.context.addClass('error');
        }

    });


    // Prevent the default action when a file is dropped on the window
    $(document).on('drop dragover', function (e) {
        e.preventDefault();
    });

    // Helper function that formats the file sizes
    function formatFileSize(bytes) {
        if (typeof bytes !== 'number') {
            return '';
        }

        if (bytes >= 1000000000) {
            return (bytes / 1000000000).toFixed(2) + ' GB';
        }

        if (bytes >= 1000000) {
            return (bytes / 1000000).toFixed(2) + ' MB';
        }

        return (bytes / 1000).toFixed(2) + ' KB';
    }

});