Dropzone Submit Button on Upload

You need to:

1. Add a button:

   <button type="submit" id="button" class="btn btn-primary">Submit</button>
   

2. Tell Dropzone not to automatically upload the file when you drop it, as it will by default. That’s done with the autoProcessQueue config option:

   autoProcessQueue: false
   

3. Since Dropzone will now not auto-upload the files, you need to manually tell it to do that when you click your button. So you need an event handler for that button click, which tells Dropzone to do the upload:

   $("#button").click(function (e) {
       e.preventDefault();
       myDropzone.processQueue();
   });
   

4. That will just POST the uploaded file, without any of your other input fields. You probably want to post all fields, eg your refCampaignID, a CSRF token if you have one, etc. To do that, you need to copy them into the POST before sending. Dropzone has a sending event which is called just before each file is sent, where you can add a callback:

   this.on('sending', function(file, xhr, formData) {
       // Append all form inputs to the formData Dropzone will POST
       var data = $('form').serializeArray();
       $.each(data, function(key, el) {
           formData.append(el.name, el.value);
       });
   });
   

Putting it all together:

Dropzone.options.frmTarget = {
    autoProcessQueue: false,
    url: 'upload_files.php',
    init: function () {

        var myDropzone = this;

        // Update selector to match your button
        $("#button").click(function (e) {
            e.preventDefault();
            myDropzone.processQueue();
        });

        this.on('sending', function(file, xhr, formData) {
            // Append all form inputs to the formData Dropzone will POST
            var data = $('#frmTarget').serializeArray();
            $.each(data, function(key, el) {
                formData.append(el.name, el.value);
            });
        });
    }
}