Reinitialize/Reset dropzone after form is submitted

this.on("complete", function(file) { 
   this.removeAllFiles(true); 
})

write the above code in INIT function.

this removes all files in dropzone and RESETS the dropzone to initial state.

http://www.dropzonejs.com/#event-reset

Finally, I solved the issue myself. At first I remove the form from its parents element.It removed the existing dropzone instance.Then I create the form using the jQuery and reinitialize the dropzone again. Here is my complete code

 // To reset dropzone before popup load
    var resetDropzone = function () {

        $('#drop-zone-container').empty();

        var $form = makeElement('form', {
            action: window.pg.constants.url.SETTLEMENT_BASE_URL,
            method: 'post',
            id: 'settlement-proof-form',
            class: 'dropzone'
        });

        $('#drop-zone-container').append($form);

        var settlmentProofDropZone;
        $("#settlement-proof-form").dropzone({
            acceptedFiles: pg.constants.ACCEPTED_FORMAT,
            maxFilesize: pg.constants.ATTACHMENT_MAX_FILE_SIZE, //In MB
            maxFiles: pg.constants.ATTACHMENT_MAX_SIZE,
            addRemoveLinks: true,
            removedfile: function (file) {
                if (file.xhr.responseText.length > 0) {
                    var fileId = JSON.parse(file.xhr.responseText).id;
                    $.ajax({
                        url: pg.constants.url.SETTLEMENT_BASE_URL + fileId,
                        method: 'DELETE',
                        dataType: "json",
                        success: function (result) {
                            $('#uploaded_attachment').val($("#uploaded_attachment").val().replace(result.id + ',', ""));
                            $('#settlement_proof_status span').fadeOut(0);
                            var _ref;
                            return (_ref = file.previewElement) != null ? _ref.parentNode.removeChild(file.previewElement) : void 0;

                        },
                        error: function () {
                            $('#settlement_proof_status').text(I18n.t('attachment_deletion_error')).fadeIn();
                        }

                    });
                }

            },
            init: function () {
                settlmentProofDropZone = this;

                this.on("success", function (file, message) {
                    appendContent(message.attachment.url, message.id);
                });
            }
        });

    };

    function makeElement(element, options) {
        var $formField = document.createElement(element);
        $.each(options, function (key, value) {
            if (key === 'innerHTML') {
                $formField.innerHTML = value;
            }
            else {
                $formField.setAttribute(key, value);
            }
        });
        return $formField;
    }
});

Try this:

//DropZone Initiation Section
init: function() {
    this.on('success', function(file, json) {
    });

    this.on('addedfile', function(file) {
    });

    this.on('drop', function(file) {
    });

    this.on('removedfile', function(file) {
    });

    this.on('complete', function(file) {
    });

    this.on('error', function(file) {
    });

    this.on('resetFiles', function() {
        if(this.files.length != 0){
            for(i=0; i<this.files.length; i++){
                this.files[i].previewElement.remove();
            }
            this.files.length = 0;
        }
    });
}

function JS_ClearDropZone() {
    //DropZone Object Get
    var objDZ = Dropzone.forElement("div#objDropzone");
    //"resetFiles" Event Call
    objDZ.emit("resetFiles");
}

Every answer here is incredibly complicated. I have a dropzone in a modal with some ajax to draw the uploaded/complete file on the page. If the user adds ANOTHER image to the gallery, I wanted to reset the dropzone in that modal without refreshing the page. The answer? See my solution here https://stackoverflow.com/a/45247184/179571