Using XPath To Shred HTML

Shannon Lowder shows off the HTML Agility Path project to help him parse the contents of webpages:

Let’s say we wanted the table.  We could use the XPath /html/body/table to retrieve it. We can also use XPath to refer to a collection.  Let’s say we wanted all the rows. We would use the XPath /html/body/table/tr. We would get a collection of three rows.  Notice the XPath looks a lot like a Linux or windows folder path.  That’s the idea of XPath!

I would like to point out a couple of extra points.  First, XPath is case sensitive.  So if I had tried to use /html/body/table/TR, I would find no nodes.

Second, you can use “short hand” in your XPath queries.  //body/table/tr would get you to the same place /html/body/table/tr did.

This intro is part of a series Shannon has started on scraping data from websites.

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