javascript_file_upload.js

var dropHandler = function(evt){
    evt.preventDefault();
    var files = evt.originalEvent.dataTransfer.files;

    var formData = new FormData();
    formData.append("file2upload", files[0]);

    var req = {
        url: "/sendfile",
        method: "post",
        processData: false,
        contentType: false,
        data: formData
    };

    var promise = $.ajax(req);
};