默认情况下，您无法使用Ajax上传文件((

By default you cant upload a file using ajax,( Why can't I upload files asynchronously? )

但是有一些技术，包括您可以使用的iframe或Flash插件

but there are a few techinques, including iframes or flash plugins you could use

• 如何异步上传文件?

什么是***的多重文件JavaScript/Flash文件上传器?

希望这会有所帮助