FileList 没有删除条目的 API:

FileList has no API to remove entries:

https://developer.mozilla.org/en/DOM/FileList

但是，您可以使用 XHR2 和 AJAX 重建文件上传器并在那里过滤内容.这意味着要进行 XHR2 和 AJAX 上传，不适合传统的

However you can reconstruct File uploader using XHR2 and AJAX and filter in content there. This implies doing XHR2 and AJAX upload and is not suitable for traditional <form> uploads.

https://developer.mozilla.org/en/Using_files_from_web_applications