$(function () {
    Dropzone.options.myDropzone = {
        init: function() {
            this.on("addedfile", function(file) {

                // Create the remove button
                var removeButton = Dropzone.createElement("<button class='btn'>Remove file</button>");


                // Capture the Dropzone instance as closure.
                var _this = this;

                // Listen to the click event
                removeButton.addEventListener("click", function(e) {
                    // Make sure the button click doesn't submit the form:
                    e.preventDefault();
                    e.stopPropagation();

                    // Remove the file preview.
                    _this.removeFile(file);
                    // If you want to the delete the file on the server as well,
                    // you can do the AJAX request here.
                });

                // Add the button to the file preview element.
                file.previewElement.appendChild(removeButton);
            });
        }
    };
});