JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://rawgithub.com/jquery/jquery-ui/master/ui/jquery.ui.widget.js"></script>
<script src="http://rawgithub.com/blueimp/jQuery-File-Upload/master/js/jquery.fileupload.js"></script>
<form action="/echo/json/" method="POST">
    <input name="file1[]" type="file" multiple />
    <br />
    
    <input name="file2[]" type="file" multiple />
    <br />
    
    <input name="file3[]" type="file" multiple />
    <br />
 
    <button>send by fileupload send api</button>
</form>

JavaScript

$(document).ready(function(){
    var filesList = [],
        paramNames = [],
        elem = $("form");
    file_upload = elem.fileupload({
        formData:{extra:1},
        autoUpload: false,
        fileInput: $("input:file"),
    }).on("fileuploadadd", function(e, data){
        filesList.push(data.files[0]);
        paramNames.push(e.delegatedEvent.target.name);
    });

    $("button").click(function(e){
        e.preventDefault();
        file_upload.fileupload('send', {files:filesList, paramName: paramNames});
    })
})