If you serve an XHTML document with a MIME type of application/xhtml+xml, Internet Explorer will prompt you to download the file, because it doesn't know how to handle the file.

如果你使用application/xhtml+xml作为MIME类型来定义一个XHTML文档，Internet Explorer将提醒你下载这个文件，因为它不知道怎样处理这一类型的文件。

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Allows a file to be opened with an internal Root Explorer function, as a generic type (text, video etc) or with a specific app.

实现用程序内部的查看器或指定程序直接打开常见的文本、视频等类型文件。

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