cannot reupload file on change angular code example

Example 1: same file select angular second time not selected

@ViewChild('fileInput') fileInput: any;
...
uploadFile() {
  this.uploader.uploadAll();
  this.fileInput.nativeElement.value = '';
}

Example 2: same file select angular second time not selected

<input #fileInput id="file" type="file" ng2FileSelect [uploader]="uploader" (change)="uploadFile()"/>