您必须使用HTML5文件API。关于它的更多信息，你可以找到这里。我不能提供任何code为例，主要是因为我不知道你的服务器的外观。你必须给用户一个交易令牌，他将不得不向您发送的块号，块数据和令牌，这样你就可以重新组装在服务器上。

You have to use the HTML5 file API. More info about it you can find here. I can't provide any code example, mainly because i don't know how your server looks. You have to give the user a transaction token, and he will have to send you the chunk number, chunk data and the token, so you'll be able to re-assemble it on the server.