Here is a way to append file to FormData :
append
FormData
var data = new FormData(); jQuery.each($(\'#file\')[0].files, function(i, file) {
I know this thread is old but I just found this : https://developer.mozilla.org/en-US/docs/Web/API/FormData/delete
I'm sur it could help. You can use formData.delete(name) to delete the entry of formData with "name" key.
formData.delete(name)