Lucene只能为纯文本文档建立索引，因此我们需要找到一种方法将纯文本从上面提到的那些富文档格式的文档中提取出来，然后将其提供给Lucene。

Lucene can index only plain text documents, so we need a way to extract the plain text from a rich document format like those above and feed it into Lucene.

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许多回复文本文档都可以将其富文本或纯文本正文字段附加到电子邮件消息后。

Any number of response text documents can have their rich or plain text body field appended to an email message.

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对于富文本文档，创建视图操作按钮，执行查找以及将回复连接到单个消息中。

For rich text documents, create a view action button that performs the lookup and concatenates the responses into a single message.

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