fileChange(event) {
        let fileList: FileList = event.target.files;
        if(fileList) {
            let file: File = fileList[0];
            let formData:FormData = new FormData();
            formData.append('uploadFile', file, file.name);
            let headers = new Headers();
            /** No need to include Content-Type in Angular 4 */
            headers.append('Content-Type', 'multipart/form-data');
            headers.append('Accept', 'application/json');
            let options = new RequestOptions({ headers: headers });
            this.http.post(`assets/Files/info.txt`, formData, options)
                .map(res => res.json())
                .catch(error => Observable.throw(error))
                .subscribe(
                    data => console.log(fileList),
                    error => console.log(error)
                )
             }
          }