vuejs verwendet Vue-Ressource, um den Ajax-Anfragecode zu senden:

methods: {
                fillIn: function (index, n) {
                    var formData = new FormData();
                    var itemId=this.items[index].id;
                    this.items[index].publishing_days = n;
                    formData.append('publishing_days', n);

                    this.$http.patch('/article/'+itemId, formData,{
                        before(request) {
                            if (this.previousRequest) {
                                this.previousRequest.abort();
                            }
                            this.previousRequest = request;
                        }
                    }).then((response) => {

                    }, (response) => {

                    });
                }
            }

Dies ist ein Screenshot der von der Ajax-Anfrage gesendeten Daten:

ArticleController

    public function update(Request $request, $id)
    {
        $article = Article::findOrFail($id);
        dd($article);
        dd($request->publishing_days); 
    }

Frage: Das Ergebnis von
dd($request->publishing_days); ist null, was ist los?