JQuery: 'Uncaught TypeError: Illegal invocation' at ajax request - several elements

Question

I have two select elements, A and B: when A\'s selected option changes, B\'s options must be updated accordingly. Each element in A implies many elements in B, it\'s a one-t

Answer 1

$.ajax({
                    url:"",
                    type: "POST",
                    data: new FormData($('#uploadDatabaseForm')[0]),
                    contentType:false,
                    cache: false,
                    processData:false,
                    success:function (msg) {}
                  });