使用 C# 获取 HTML 文档中文本周围的标签

Question

I would like to search an HTML file for a certain string and then extract the tags. Given:

<div_outer><div_inner>Happy birthday<div><div>

I would like to search the HTML for "Happy birthday" then have a function return some sort of tag structure: this is the innermost tag, this is the tag outside that one, etc. So, <div_inner></div> then <div_outer></div> .

Any ideas? I am thinking HTMLAgilityPack but I haven't been able to figure out how to do it.

Thanks as always, guys.

Answer 1

The HAP is a good place indeed for this.

You can use the OuterHtml and Parent properties of a Node to get the enclosing elements and markup.

Answer 2

You could use xpath for this. I use //*[text()='Happy birthday'][1]/ancestor-or-self::* expression which finds a first (for simplicity) node which text content is Happy birthday , and then returns all the ancestors (parent, grandparent, etc.) of this node and the node itself:

var doc = new HtmlDocument();
doc.LoadHtml("<div_outer><div_inner>Happy birthday<div><div>");

var ancestors = doc.DocumentNode
    .SelectNodes("//*[text()='Happy birthday'][1]/ancestor-or-self::*")
    .Reverse()
    .ToList();

It seems that the order of the nodes returned is the order the nodes found in the document, so I used Enumerable.Reverse method to reverse it.

This will return 2 nodes: div_inner and div_outer .