XPath selecting between comments multiple times

问题

We need to read node between HTML comments:

<html>
<!-- comment 1 -->
 <div>some text</div>
 <div><p>Some more elements</p></div>
<!-- end content -->

<!-- comment 2 -->
 <div>some text</div>
 <div><p>Some more elements</p>
 <!-- end content -->
 </div>
</html>

I tried using the below XPath:

//*[preceding-sibling::comment()[contains(., 'comment 1')]][following-sibling::comment()[contains(., 'end content')]]

It works fine for first comment i.e. comment 1 but not working for second comment following is the XPath for the same

//*[preceding-sibling::comment()[contains(., 'comment 2')]][following-sibling::comment()[contains(., 'end content')]]

I am using HTML Agility Pack with below code:

var nodes = document.SelectNodes("//*[preceding-sibling::comment()[contains(., 'comment 1')]][following-sibling::comment()[contains(., 'InstanceEndEditable')]]");

string allHtml = nodes[0].OuterHtml;

If I change "comment 1" to "comment 2" in above code then it is not giving any result.

回答1:

Add a predicate that states that you want the first preceding comment and the first following comment.

So, for example, to get the contents between the comments that starts with "comment 1":

//*[preceding-sibling::comment()[1][contains(., 'comment 1')]]
   [following-sibling::comment()[1][contains(., 'end content')]]

Similarly, to get the contents between the comments that starts with "comment 2":

//*[preceding-sibling::comment()[1][contains(., 'comment 2')]]
   [following-sibling::comment()[1][contains(., 'end content')]]

来源：https://stackoverflow.com/questions/26404345/xpath-selecting-between-comments-multiple-times

标签

html

xpath

html-agility-pack