如何在滚动的DIV中获取当前活动文本

Question

芯片式DIV包含需要滚动的段落

例如

<div id="text" style='overflow:scroll;width:200px;height:200px'>

<div style='font-size:64px;'>BIG TEXT</div> 
Lorem Ipsum is simply dummy text of the printing and typesetting 
industry. Lorem Ipsum    has been the industry's standard dummy text ever  
since the 1500s, when an unknown printer took a galley of type and scrambled it 
to make a type specimen book. It has survived not only five centuries, but also 
the leap into electronic typesetting, remaining essentially unchanged.
It was popularised in the 1960s with the release of Letraset sheets 
containing Lorem Ipsum passages, and more recently with desktop publishing software 
like Aldus PageMaker 
including versions of Lorem Ipsum.

</div>

当滚动条移动时,文本更改(由于overflow:scroll),是否可以仅选择当前视图端口中显示的文本？

示例:http://jsfiddle.net/cxgkY/15/

更新:内部HTML可能包含可变大小的文本

Answer 1

这是一个小演示，应该可以满足您的期望：小链接（也适用于可变大小）。这个想法是自动span为每个单词创建一个单独的单词，然后，每次div滚动时，检查哪些span单词是可见的（通过检查它们的top偏移量），从而更新文档选择范围。如果有任何不清楚的地方，我很乐意解释。