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EDIT (Oct 2019):

6 years later and jQuery File Upload is clearly still driving folks insane. If you're finding little solace in the answers here, try a search of NPM for a modern alternative. It's not worth the hassle, I promise.

I recommended Uploadify in the previous edit but, as a commenter pointed out, they no longer appear to offer a free version. Uploadify was so 2013 anyway.


EDIT:

This still seems to be getting traffic so I'll explain what I ended up doing. I eventually got the plugin working by following the tutorial in the accepted answer. However, jQuery File Upload is a real hassle and if you're looking for a simpler file upload plugin, I would highly recommend [Uploadify](http://www.uploadify.com). As an answer pointed out, it is only free for non-commercial use.

Background

I'm trying to use blueimp's jQuery File Upload to allow users to upload files. Out of the box it works perfectly, following the setup instructions. But to use it practically on my website, I want to be able to do a couple of things:

  • Include the uploader on any of my existing pages
  • Change the directory for uploaded files

All the files for the plugin are located in a folder under the root.

I've tried...

  • Moving the demo page into the root and updating the paths for the necessary scripts
  • Changing the 'upload_dir' and 'upload_url' options in the UploadHandler.php file as suggested here.
  • Changing the URL in the second line of the demo javascript

In all cases, the preview shows, and the progress bar runs, but the files fail to upload, and I get this error in the console: Uncaught TypeError: Cannot read property 'files' of undefined. I don't understand how all the parts of the plugin work which is making it difficult to debug.

Code

The javascript in the demo page:

$(function () {
'use strict';
// Change this to the location of your server-side upload handler:
var url = 'file_upload/server/php/UploadHandler.php',
    uploadButton = $('<button/>')
        .addClass('btn')
        .prop('disabled', true)
        .text('Processing...')
        .on('click', function () {
            var $this = $(this),
                data = $this.data();
            $this
                .off('click')
                .text('Abort')
                .on('click', function () {
                    $this.remove();
                    data.abort();
                });
            data.submit().always(function () {
                $this.remove();
            });
        });
$('#fileupload').fileupload({
    url: url,
    dataType: 'json',
    autoUpload: false,
    acceptFileTypes: /(\.|\/)(gif|jpe?g|png)$/i,
    maxFileSize: 5000000, // 5 MB
    // Enable image resizing, except for Android and Opera,
    // which actually support image resizing, but fail to
    // send Blob objects via XHR requests:
    disableImageResize: /Android(?!.*Chrome)|Opera/
        .test(window.navigator.userAgent),
    previewMaxWidth: 100,
    previewMaxHeight: 100,
    previewCrop: true
}).on('fileuploadadd', function (e, data) {
    data.context = $('<div/>').appendTo('#files');
    $.each(data.files, function (index, file) {
        var node = $('<p/>')
                .append($('<span/>').text(file.name));
        if (!index) {
            node
                .append('<br>')
                .append(uploadButton.clone(true).data(data));
        }
        node.appendTo(data.context);
    });
}).on('fileuploadprocessalways', function (e, data) {
    var index = data.index,
        file = data.files[index],
        node = $(data.context.children()[index]);
    if (file.preview) {
        node
            .prepend('<br>')
            .prepend(file.preview);
    }
    if (file.error) {
        node
            .append('<br>')
            .append(file.error);
    }
    if (index + 1 === data.files.length) {
        data.context.find('button')
            .text('Upload')
            .prop('disabled', !!data.files.error);
    }
}).on('fileuploadprogressall', function (e, data) {
    var progress = parseInt(data.loaded / data.total * 100, 10);
    $('#progress .bar').css(
        'width',
        progress + '%'
    );
}).on('fileuploaddone', function (e, data) {
    $.each(data.result.files, function (index, file) {
        var link = $('<a>')
            .attr('target', '_blank')
            .prop('href', file.url);
        $(data.context.children()[index])
            .wrap(link);
    });
}).on('fileuploadfail', function (e, data) {
    $.each(data.result.files, function (index, file) {
        var error = $('<span/>').text(file.error);
        $(data.context.children()[index])
            .append('<br>')
            .append(error);
    });
}).prop('disabled', !$.support.fileInput)
    .parent().addClass($.support.fileInput ? undefined : 'disabled');
});

I'm surprised by the lack of documentation; it seems like it should be a simple thing to change. I would appreciate if someone could explain how to do this.
Austen
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    Good question format. Nice to see organization. – jdero Jul 29 '13 at 21:41
  • print 'e' and 'data' in the console right before the error line, what are the values? – john 4d5 Aug 02 '13 at 12:26
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    Uploadi**fy** is MIT license e.g. it is completely free. However, Uploadi**Five** from the same [dev/website](http://www.uploadify.com/download/) is $5-$100 depending on usage – MartinJH Jun 29 '15 at 15:10
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    In two years the jQuery-File-Upload documentation hasn't gotten any better. Argh. – Chuck Le Butt Jul 15 '15 at 16:29
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    @MartinJH there may have been an uploadify at some point, but as of now there's only one - the paid uploadiFive version. And there's no demo either; it's but a video. Poor form. – Steve Horvath Oct 09 '19 at 22:58
  • @SteveHorvath thanks for pointing this out! I updated the question. – Austen Oct 10 '19 at 23:10
  • [Uploadify](https://github.com/RonnieSan/uploadify/blob/master/LICENSE) is open source now - updated Dec 2019 – Clark Baker Jan 29 '20 at 23:07

11 Answers11

74

I was looking for a similar functionality some days back and came across a good tutorial on tutorialzine. Here is an working example. Complete tutorial can be found here.

Simple form to hold the file upload dialogue:

<form id="upload" method="post" action="upload.php" enctype="multipart/form-data">
  <input type="file" name="uploadctl" multiple />
  <ul id="fileList">
    <!-- The file list will be shown here -->
  </ul>
</form>

And here is the jQuery code to upload the files:

$('#upload').fileupload({

  // This function is called when a file is added to the queue
  add: function (e, data) {
    //This area will contain file list and progress information.
    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. This part can be ignored, if you are showing progress in some other way.
    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');
        }
    }
});
//Helper function for calculation of progress
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';
}

And here is the PHP code sample to process the data:

if($_POST) {
    $allowed = array('jpg', 'jpeg');

    if(isset($_FILES['uploadctl']) && $_FILES['uploadctl']['error'] == 0){

        $extension = pathinfo($_FILES['uploadctl']['name'], PATHINFO_EXTENSION);

        if(!in_array(strtolower($extension), $allowed)){
            echo '{"status":"error"}';
            exit;
        }

        if(move_uploaded_file($_FILES['uploadctl']['tmp_name'], "/yourpath/." . $extension)){
            echo '{"status":"success"}';
            exit;
        }
        echo '{"status":"error"}';
    }
    exit();
}

The above code can be added to any existing form. This program automatically uploads images, once they are added. This functionality can be changed and you can submit the image, while you are submitting your existing form.

Updated my answer with actual code. All credits to original author of the code.

Source: http://tutorialzine.com/2013/05/mini-ajax-file-upload-form/

Jack
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Subrat Pattnaik
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    Can you copy the important parts of that tutorial here, so if it disappears your answer is still useful? –  Sep 13 '13 at 03:29
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    but be careful not to plagiarize – tacaswell Sep 13 '13 at 04:28
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    ATTENTION : To anyone using the PHP code snippet remove the `if($_POST)` statement. POST is supposed to be empty the file content is sent in `$_FILES['upfile']['tmp_name']`. Hopefully this saves someone some time. – Edward Jul 09 '15 at 01:07
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    Found another http://www.c-sharpcorner.com/UploadFile/da55bf/multiple-files-upload-using-jquery-ajax-and-jqueryui-progres/ – Rush.2707 Dec 26 '16 at 10:09
  • can anyone suggest me what are the js/jquery files needed to run the above script – Manasa Jun 14 '17 at 07:59
  • can anyone suggest me what are the js/jquery files are needed to run the above script – Manasa Jun 14 '17 at 08:02
  • The original tutorial suggests using libraries: https://github.com/aterrien/jQuery-Knob and https://github.com/blueimp/jQuery-File-Upload along with jQuery. However, you can skip some of those, if you do not want to exactly replicate the UI. – Subrat Pattnaik Jun 27 '17 at 13:13
  • this tutorial came from 2013, awesome. Very useful :D – May'Habit Oct 03 '19 at 07:36
  • how do i remove and upload each file? – May'Habit Oct 10 '19 at 10:08
31

I've just spent 2 hours battling with jQuery Upload but gave up because of the amount of dependencies (I had 13 JS files included to get all the bells and whistles).

I did a bit more searching and came across a neat project called Dropzone.js, which does not have any dependencies.

The author has also created a bootstrap demo which was inspired by the jQuery File Upload plugin.

I hope this saves someone else some time.

Tim
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    Important thing to note: Dropzone.js looks nice, but it only supports from IE10 and higher. jQuery file upload supports from IE6 ;) – Nickvda Aug 31 '15 at 11:22
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    jQuery File Upload is just impossible to make it work... I sent many hours trying because it has very nice features, but at the last minute my soul was only filled with agony!!! What a dispair!!! Then I saw your post about [Dropzone.js](http://www.dropzonejs.com/) and in 5 minutes I make it work and the way that I wanted! You saved me... – rigon Oct 16 '15 at 19:05
  • Can't thank you enough, I have spent nearly 12 hours in getting [jQuery-FIle-Upload](https://github.com/blueimp/jQuery-File-Upload) working the way I want and finally I stumbled upon this question. You saved me. – ndd Apr 25 '16 at 17:51
  • here is a database driven jquery file upload example: https://github.com/CodeHeight/ImageLibrary – JoshYates1980 Jun 12 '17 at 20:32
  • I spent 3 days but I still can not custom their code – May'Habit Oct 08 '19 at 02:04
  • helpful indeed i spent close to 8 hours working around trying to customize jquery file upload. – logicalrap Aug 14 '20 at 17:03
4

I also struggled with this but got it working once I figured out how the paths work in UploadHandler.php: upload_dir and upload_url are about the only settings to look at to get it working. Also check your server error logs for debugging information.

3

Check out the Image drag and drop uploader with image preview using dropper jquery plugin.

HTML

<div class="target" width="78" height="100"><img /></div>

JS

$(".target").dropper({
    action: "upload.php",

}).on("start.dropper", onStart);
function onStart(e, files){
console.log(files[0]);

    image_preview(files[0].file).then(function(res){
$('.dropper-dropzone').empty();
//$('.dropper-dropzone').css("background-image",res.data);
 $('#imgPreview').remove();        
$('.dropper-dropzone').append('<img id="imgPreview"/><span style="display:none">Drag and drop files or click to select</span>');
var widthImg=$('.dropper-dropzone').attr('width');
        $('#imgPreview').attr({width:widthImg});
    $('#imgPreview').attr({src:res.data});

    })

}

function image_preview(file){
    var def = new $.Deferred();
    var imgURL = '';
    if (file.type.match('image.*')) {
        //create object url support
        var URL = window.URL || window.webkitURL;
        if (URL !== undefined) {
            imgURL = URL.createObjectURL(file);
            URL.revokeObjectURL(file);
            def.resolve({status: 200, message: 'OK', data:imgURL, error: {}});
        }
        //file reader support
        else if(window.File && window.FileReader)
        {
            var reader = new FileReader();
            reader.readAsDataURL(file);
            reader.onloadend = function () {
                imgURL = reader.result;
                def.resolve({status: 200, message: 'OK', data:imgURL, error: {}});
            }
        }
        else {
            def.reject({status: 1001, message: 'File uploader not supported', data:imgURL, error: {}});
        }
    }
    else
        def.reject({status: 1002, message: 'File type not supported', error: {}});
    return def.promise();
}

$('.dropper-dropzone').mouseenter(function() {
 $( '.dropper-dropzone>span' ).css("display", "block");
});

$('.dropper-dropzone').mouseleave(function() {
 $( '.dropper-dropzone>span' ).css("display", "none");
});

CSS

.dropper-dropzone{
    width:78px;
padding:3px;
    height:100px;
position: relative;
}
.dropper-dropzone>img{
    width:78px;
    height:100px;
margin-top=0;
}

.dropper-dropzone>span {
    position: absolute;
    right: 10px;
    top: 20px;
color:#ccc;


}

.dropper .dropper-dropzone{

padding:3px !important    
}

Demo Jsfiddle

tvshajeer
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2

This is good Angular plugin for uploading files, and its free!

angular file upload

Sahip
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    Hi. Please don't post links as answers, if the site goes offline or the link changes, your answer will become useless. Instead, use the info on the site to build your answer and use the link as reference only. Thanks. – Cthulhu Mar 29 '16 at 16:09
1

You can use uploadify this is the best multiupload jquery plugin i have used.

The implementation is easy, the browser support is perfect.

CORSAIR
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    You can use HTML 5 Version :) – CORSAIR Feb 20 '14 at 09:16
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    If I'm not mistaken, the html5 version of uploadify is not free. It costs $5. http://www.uploadify.com/download/ – kingsfoil Nov 04 '14 at 18:02
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    But, this is only 5$ not 500. – CORSAIR Nov 06 '14 at 08:26
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    Bear in mind, if you want to use uploadify for commercial purposes you need to buy the commercial license ($100) http://www.uploadify.com/download/download-uploadifive-commercial/ – Tim Feb 10 '15 at 10:37
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    Uploadify is MIT license (free), UploadiFive is $5-$100 – MartinJH Jun 29 '15 at 15:07
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    For anyone interested, Uploadify = Flash version, UploadiFive = HTML5 version. – Chuck Le Butt Jul 15 '15 at 16:27
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    Also for anyone interested: the API for each of the 2 plugins is different. We wound up wrapping both in our own plugin, that translates the settings as required. More recently we just wrote our own uploader as Uploadify had too many issues with multiple uploads on a page. – iCollect.it Ltd Sep 24 '16 at 18:55
1

I struggled with this plugin for a while on Rails, and then someone gemified it obsoleting all the code I had created.

Although it looks like you're not using this in Rails, however if anyone is using it checkout this gem. The source is here --> jQueryFileUpload Rails.

Update:

In order to satisfy the commenter I've updated my answer. Essentially "use this gem, here is the source code" If it disappears then do it the long way.

engineerDave
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1

Hi try bellow link it is very easy. I've been stuck for long time and it solve my issue in few minutes. http://simpleupload.michaelcbrook.com/#examples

Iftikhar Khan
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1

Droply.js is perfect for this. It's simple and comes pre-packaged with a demo site that works out of the box.

Geremia
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1

it's 2021 and here's a fantastically easy plugin to upload anything:

https://pqina.nl/filepond/?ref=pqina

add your element:

<input type="file" 
class="filepond"
name="filepond" 
multiple 
data-allow-reorder="true"
data-max-file-size="3MB"
data-max-files="3">

Register any additional plugins:

  FilePond.registerPlugin(
FilePondPluginImagePreview,  
FilePondPluginImageExifOrientation,  
FilePondPluginFileValidateSize,  
FilePondPluginImageEdit);

Then wire in the element:

// Select the file input and use 
// create() to turn it into a pond
FilePond.create(
  document.querySelector('input'),

  // Use Doka.js as image editor
  imageEditEditor: Doka.create({
    utils: ['crop', 'filter', 'color']
  })
);

I use this with the additional Doka image editor to upload and transform images at https://www.yoodu.co.uk

crazy simple to setup and the guys who run it are great at support.

As you can tell I'm a fanboy.

Alex Stephens
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0

For the UI plugin, with jsp page and Spring MVC..

Sample html. Needs to be within a form element with an id attribute of fileupload

    <!-- The fileupload-buttonbar contains buttons to add/delete files and start/cancel the upload -->
<div class="fileupload-buttonbar">
    <div>
        <!-- The fileinput-button span is used to style the file input field as button -->
        <span class="btn btn-success fileinput-button">
            <i class="glyphicon glyphicon-plus"></i>
            <span>Add files</span>
            <input id="fileuploadInput" type="file" name="files[]" multiple>
        </span>
        <%-- https://stackoverflow.com/questions/925334/how-is-the-default-submit-button-on-an-html-form-determined --%>
        <button type="button" class="btn btn-primary start">
            <i class="glyphicon glyphicon-upload"></i>
            <span>Start upload</span>
        </button>
        <button type="reset" class="btn btn-warning cancel">
            <i class="glyphicon glyphicon-ban-circle"></i>
            <span>Cancel upload</span>
        </button>
        <!-- The global file processing state -->
        <span class="fileupload-process"></span>
    </div>
    <!-- The global progress state -->
    <div class="fileupload-progress fade">
        <!-- The global progress bar -->
        <div class="progress progress-striped active" role="progressbar" aria-valuemin="0" aria-valuemax="100">
            <div class="progress-bar progress-bar-success" style="width:0%;"></div>
        </div>
        <!-- The extended global progress state -->
        <div class="progress-extended">&nbsp;</div>
    </div>
</div>
<!-- The table listing the files available for upload/download -->
<table role="presentation" class="table table-striped"><tbody class="files"></tbody></table>

<link rel="stylesheet" type="text/css" href="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/css/jquery.fileupload.css">
<link rel="stylesheet" type="text/css" href="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/css/jquery.fileupload-ui.css">

<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/js/vendor/jquery.ui.widget.js"></script>
<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/js/jquery.iframe-transport.js"></script>
<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/js/jquery.fileupload.js"></script>
<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/js/jquery.fileupload-process.js"></script>
<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/js/jquery.fileupload-validate.js"></script>
<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-file-upload-9.14.2/js/jquery.fileupload-ui.js"></script>

<script type="text/javascript">
    $(document).ready(function () {
            var maxFileSizeBytes = ${maxFileSizeBytes};
        if (maxFileSizeBytes < 0) {
            //-1 or any negative value means no size limit
            //set to undefined
            //https://stackoverflow.com/questions/5795936/how-to-set-a-javascript-var-as-undefined
            maxFileSizeBytes = void 0;
        }

        //https://github.com/blueimp/jQuery-File-Upload/wiki/Options
        //https://stackoverflow.com/questions/34063348/jquery-file-upload-basic-plus-ui-and-i18n
        //https://stackoverflow.com/questions/11337897/how-to-customize-upload-download-template-of-blueimp-jquery-file-upload
        $('#fileupload').fileupload({
            url: '${pageContext.request.contextPath}/app/uploadResources.do',
            fileInput: $('#fileuploadInput'),
            acceptFileTypes: /(\.|\/)(jrxml|png|jpe?g)$/i,
            maxFileSize: maxFileSizeBytes,
            messages: {
                acceptFileTypes: '${fileTypeNotAllowedText}',
                maxFileSize: '${fileTooLargeMBText}'
            },
            filesContainer: $('.files'),
            uploadTemplateId: null,
            downloadTemplateId: null,
            uploadTemplate: function (o) {
                var rows = $();
                $.each(o.files, function (index, file) {
                    var row = $('<tr class="template-upload fade">' +
                            '<td><p class="name"></p>' +
                            '<strong class="error text-danger"></strong>' +
                            '</td>' +
                            '<td><p class="size"></p>' +
                            '<div class="progress progress-striped active" role="progressbar" aria-valuemin="0" aria-valuemax="100" aria-valuenow="0">' +
                            '<div class="progress-bar progress-bar-success" style="width:0%;"></div></div>' +
                            '</td>' +
                            '<td>' +
                            (!index && !o.options.autoUpload ?
                                    '<button class="btn btn-primary start" disabled>' +
                                    '<i class="glyphicon glyphicon-upload"></i> ' +
                                    '<span>${startText}</span>' +
                                    '</button>' : '') +
                            (!index ? '<button class="btn btn-warning cancel">' +
                                    '<i class="glyphicon glyphicon-ban-circle"></i> ' +
                                    '<span>${cancelText}</span>' +
                                    '</button>' : '') +
                            '</td>' +
                            '</tr>');
                    row.find('.name').text(file.name);
                    row.find('.size').text(o.formatFileSize(file.size));
                    if (file.error) {
                        row.find('.error').text(file.error);
                    }
                    rows = rows.add(row);
                });
                return rows;
            },
            downloadTemplate: function (o) {
                var rows = $();
                $.each(o.files, function (index, file) {
                    var row = $('<tr class="template-download fade">' +
                            '<td><p class="name"></p>' +
                            (file.error ? '<strong class="error text-danger"></strong>' : '') +
                            '</td>' +
                            '<td><span class="size"></span></td>' +
                            '<td>' +
                            (file.deleteUrl ? '<button class="btn btn-danger delete">' +
                                    '<i class="glyphicon glyphicon-trash"></i> ' +
                                    '<span>${deleteText}</span>' +
                                    '</button>' : '') +
                            '<button class="btn btn-warning cancel">' +
                            '<i class="glyphicon glyphicon-ban-circle"></i> ' +
                            '<span>${clearText}</span>' +
                            '</button>' +
                            '</td>' +
                            '</tr>');
                    row.find('.name').text(file.name);
                    row.find('.size').text(o.formatFileSize(file.size));
                    if (file.error) {
                        row.find('.error').text(file.error);
                    }
                    if (file.deleteUrl) {
                        row.find('button.delete')
                                .attr('data-type', file.deleteType)
                                .attr('data-url', file.deleteUrl);
                    }
                    rows = rows.add(row);
                });
                return rows;
            }
        });

    });
</script>

Sample upload and delete request handlers

    @PostMapping("/app/uploadResources")
public @ResponseBody
Map<String, List<FileUploadResponse>> uploadResources(MultipartHttpServletRequest request,
        Locale locale) {
    //https://github.com/jdmr/fileUpload/blob/master/src/main/java/org/davidmendoza/fileUpload/web/ImageController.java
    //https://github.com/blueimp/jQuery-File-Upload/wiki/Setup#using-jquery-file-upload-ui-version-with-a-custom-server-side-upload-handler
    Map<String, List<FileUploadResponse>> response = new HashMap<>();
    List<FileUploadResponse> fileList = new ArrayList<>();

    String deleteUrlBase = request.getContextPath() + "/app/deleteResources.do?filename=";

    //http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/multipart/MultipartRequest.html
    Iterator<String> itr = request.getFileNames();
    while (itr.hasNext()) {
        String htmlParamName = itr.next();
        MultipartFile file = request.getFile(htmlParamName);
        FileUploadResponse fileDetails = new FileUploadResponse();
        String filename = file.getOriginalFilename();
        fileDetails.setName(filename);
        fileDetails.setSize(file.getSize());
        try {
            String message = saveFile(file);
            if (message != null) {
                String errorMessage = messageSource.getMessage(message, null, locale);
                fileDetails.setError(errorMessage);
            } else {
                //save successful
                String encodedFilename = URLEncoder.encode(filename, "UTF-8");
                String deleteUrl = deleteUrlBase + encodedFilename;
                fileDetails.setDeleteUrl(deleteUrl);
            }
        } catch (IOException ex) {
            logger.error("Error", ex);
            fileDetails.setError(ex.getMessage());
        }

        fileList.add(fileDetails);
    }

    response.put("files", fileList);

    return response;
}

@PostMapping("/app/deleteResources")
public @ResponseBody
Map<String, List<Map<String, Boolean>>> deleteResources(@RequestParam("filename") List<String> filenames) {
    Map<String, List<Map<String, Boolean>>> response = new HashMap<>();
    List<Map<String, Boolean>> fileList = new ArrayList<>();

    String templatesPath = Config.getTemplatesPath();
    for (String filename : filenames) {
        Map<String, Boolean> fileDetails = new HashMap<>();

        String cleanFilename = ArtUtils.cleanFileName(filename);
        String filePath = templatesPath + cleanFilename;

        File file = new File(filePath);
        boolean deleted = file.delete();

        if (deleted) {
            fileDetails.put(cleanFilename, true);
        } else {
            fileDetails.put(cleanFilename, false);
        }

        fileList.add(fileDetails);
    }

    response.put("files", fileList);

    return response;
}

Sample class for generating the required json response

    public class FileUploadResponse {
    //https://github.com/blueimp/jQuery-File-Upload/wiki/Setup#using-jquery-file-upload-ui-version-with-a-custom-server-side-upload-handler

    private String name;
    private long size;
    private String error;
    private String deleteType = "POST";
    private String deleteUrl;

    /**
     * @return the name
     */
    public String getName() {
        return name;
    }

    /**
     * @param name the name to set
     */
    public void setName(String name) {
        this.name = name;
    }

    /**
     * @return the size
     */
    public long getSize() {
        return size;
    }

    /**
     * @param size the size to set
     */
    public void setSize(long size) {
        this.size = size;
    }

    /**
     * @return the error
     */
    public String getError() {
        return error;
    }

    /**
     * @param error the error to set
     */
    public void setError(String error) {
        this.error = error;
    }

    /**
     * @return the deleteType
     */
    public String getDeleteType() {
        return deleteType;
    }

    /**
     * @param deleteType the deleteType to set
     */
    public void setDeleteType(String deleteType) {
        this.deleteType = deleteType;
    }

    /**
     * @return the deleteUrl
     */
    public String getDeleteUrl() {
        return deleteUrl;
    }

    /**
     * @param deleteUrl the deleteUrl to set
     */
    public void setDeleteUrl(String deleteUrl) {
        this.deleteUrl = deleteUrl;
    }

}

See https://pitipata.blogspot.co.ke/2017/01/using-jquery-file-upload-ui.html

Timothy Anyona
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