Shulou(Shulou.com)06/01 Report--

This article will explain in detail how the wheel nipper can be used to write crawlers. The content of the article is of high quality, so the editor shares it for you as a reference. I hope you will have a certain understanding of the relevant knowledge after reading this article.

Wrote a wheel nipper, as the name implies, is used to operate HTML like tweezers.

You can use the syntax of the css selector to query or even modify the required elements in a given html. Use nipper::Document; let html = include_str! (".. / test-pages/hacker_news.html"); let document = Document::from (html)

Document.select ("tr.athing") .iter () .for_each (| athing | {let title = athing.select (".title a"); let source = title.select (".sitestr"); / / The next sibling. Let meta = athing.next (); let score = meta.select ("span.score"); let hnuser = meta.select ("a.hnuser"); let age = meta.select ("span.age"); / / The last matched element. Let comment = meta.select ("a") .last ()

Println! ("Title: {}", title.text ()); if source.exists () {println! ("> from: {}", source.text ());} if score.exists () {println! ("> {}", score.text ());} if hnuser.exists () {println! ("> by {}", hnuser.text ());} println! ("> {}", age.text ()); println! ("> {}", comment.text ()) Println! ();}); in fact, rust has had similar crate for a long time, but the syntax of these wheels is a bit tedious, and basically they can only be queried and cannot modify elements.

About can be used to write about the crawler wheel nipper is shared here, I hope that the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.