Gecko/WebKit 中的多次上传：允许在上传之前从列表中删除
我正在尝试在元素上使用新的 multiple="multiple" 属性。到目前为止，最新的 Gecko 和 WebKit 浏览器都支持这一点。我正在 Firefox 3.6 和 Chrome 5.0 上进行测试。
我可以很好地使用它，并显示文件列表（我使用 此作为指导）。然而，令人沮丧的是，用户似乎无法在添加文件后从该列表中删除文件。唯一的方法是单击“浏览...”按钮并选择一组新文件。
这是因为 元素提供的 FileList 对象是只读的，如规范中所述（无法链接 - 请参阅 W3C 网站上的 FileAPI TR）。
当然有解决方法，例如保留“已删除”项目的列表，无论如何上传所有内容，然后忽略“已删除”项目。这有点脏，如果“删除”大量文件，上传速度可能会慢得令人无法接受。
有谁知道任何其他解决方法，或者有更好的想法如何处理这个问题？目的是能够使用“多个”属性，并允许用户在上传之前从列表中删除文件。
I'm trying to use the new multiple="multiple" attribute allowable on elements. So far this is supported by recent Gecko and WebKit browsers. I'm testing on Firefox 3.6 and Chrome 5.0.
I'm able to use it fine, and display the list of files (I used this as guidance). Rather frustratingly, however, it seems like it's impossible for the user to remove files from this list after they've been added. The only way is to click the "Browse..." button and choose a new set of files.
This is because the FileList object provided by the <input> element is readonly, as mentioned in the spec (can't link - see the FileAPI TR over at the W3C's website).
There are of course workaround, like keeping a list of the "removed" items, uploading everything anyway and then ignoring the "removed" items. This is a bit dirty and could make uploading unacceptably slow if lots of files are "removed".
Does anyone know of any other workarounds, or have any better ideas how to deal with this? The aim is to be able to use the "multiple" attribute, and allow users to remove files from the list prior to uploading.
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我从 File API 的编辑 Arun Ranganathan 那里得到了答案：
我同意文件列表应该反映用户最初在文件选择器中选择的内容，并且能够将内容添加到文件列表将是一个巨大的安全漏洞。我不认为删除某些东西会导致如此巨大的安全问题，但我可以看到它如何被用于不那么积极的目的。
I got an answer from Arun Ranganathan, the editor of the File API:
I agree that the FileList should reflect what the user initially selected in the file picker and that being able to add things to the FileList would be a huge security hole. I can't see that being able to remove things would cause such huge security issues, but I can see how it could be used for less than positive purposes.