如何使用XPath在iOS上进行刮擦？

Question

我正在寻找关于如何在XPath平台上使用iOS的信息。在苹果文档中，我发现了关于XPath 苹果涂敷的信息，XPath只能在macOS上使用。

我的目标是通过XPath抓取网页，但是我找不到任何有关这方面的信息，而不是XPath，我使用HTMLKit。

有没有一种使用XPath脚本在iOS平台上抓取网页的方法？

Answer 1

我正在使用XPath 刮任何我想要的网页。对于我的实验，我采取谷歌网页，你可以采取任何其他。

对于scraping，我确实使用了埃里克·艾雅推荐的库富子进行安装，我使用了Swift软件包管理器，因为使用Cocoa和Carthage我无法安装这个库，我不知道为什么)

为了进行测试，我使用以下链接：

https://www.google.com/search?q=what+is+swift+programming+language&oq=what+is+swift+programming+lan&aqs=chrome.1.69i57j0l3j0i22i30l5j0i390.9399j0j7&sourceid=chrome&ie=UTF-8

从上面的网页，我有刮，标题，urs，和，描述。

我的代码：

extension ViewController: WKNavigationDelegate {
    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        parseHTML()
    }
    
    func parseHTML() {
        browser.evaluateJavaScript("document.documentElement.outerHTML") { (result, error) in
            guard let html = result as? String, error == nil else {
                print("Failed to get html string")
                return
            }
            
            do {
                // if encoding is omitted, it defaults to NSUTF8StringEncoding
                let doc = try HTMLDocument(string: html, encoding: String.Encoding.utf8)
 
                let classNameTitle = "LC20lb DKV0Md"
                let classNameDescription = "aCOpRe"
                let classNameURL = "yuRUbf"
                
                // XPath queries
                print("\n TITLE \n")
                for script in doc.xpath("//h3[@class='\(classNameTitle)']") {
                    print(script.stringValue)
                }
                
                print("\n Description \n")
                for script in doc.xpath("//span[@class='\(classNameDescription)']") {
                  print(script.stringValue)
                }
                
                print("\n URL \n")
                for script in doc.xpath("//div[@class='\(classNameURL)']") {
                    let a = script.firstChild(xpath: "a[contains(@href, 'http')]")
                    print(String((a?.attr("href") ?? "Something goes wrong, oops, sorry :(")))
                    
                }
              
            } catch let error {
              print(error)
            }
            
        }
    }
}

另外，对于WKWebView，我安装了一个桌面用户代理：

lazy var browser: WKWebView = {
        let view = WKWebView()
        view.navigationDelegate = self
        view.customUserAgent = "Mozilla/5.0 (Macintosh; Intel Mac OS X 11_2_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.36"
        return view
    }()

我没有描述XPath的所有语法，因为我第一次使用XPath :)链接到XPath的语法，我建议阅读完整的XPath教程。

我的网页输出：

TITLE 

Swift - Apple Developer
Pros and Cons of Swift Programming Language | AltexSoft
Swift (мова програмування) — Вікіпедія
Swift (programming language) - Wikipedia
About Swift — The Swift Programming Language (Swift 5.4)
About Swift - Swift.org
What Is Swift Programming Language and Why Should You ...
Introduction and history of Swift up to 2020 - Exyte
What is the Swift programming language, and why should I ...
What is the Swift programming language? | by Lena Charles ...

 Description 

Great First Language — Swift is a powerful and intuitive programming language for macOS, iOS, watchOS, tvOS, and beyond. Writing Swift code is interactive and fun, the syntax is concise yet expressive, and Swift includes modern features developers love. Swift code is safe by design, yet also produces software that runs lightning-fast.
29 серп. 2019 р. — Swift is a compiled programming language for iOS, macOS, watchOS, tvOS, and Linux applications. Here's what you need to know about Swift.
↑ Apple announces Swift, a new programming language for iOS. ↑ The Swift Programming Language; ↑ Lattner, Chris (June 3, 2014) ...
Swift is a general-purpose, multi-paradigm, compiled programming language developed by Apple Inc. and the open-source community, first released in 2014.
It's a safe, fast, and interactive programming language that combines the best in modern language thinking with wisdom from the wider Apple engineering ...
About Swift. Swift is a general-purpose programming language built using a modern approach to safety, performance, and software design patterns. The goal of ...
29 вер. 2020 р. — Swift was created by Apple in 2014 for iOS, watchOS, tvOS, macOS app development as a logical substitute for Objective-C, which had flaws ...
20 лист. 2020 р. — What is Swift? First released in 2014, Swift is a powerful general-purpose programming language for the Apple ecosystem. Whether you need to ...
Swift, often referred to as “Objective-C, without the C", is an open source programming language developed and maintained by Apple, and it's what the company ...
Swift is the modern programming language that was designed to overcome the several challenges of the versatile Apple programming language Objective C. It ...

 URL 

https://developer.apple.com/swift/
https://www.altexsoft.com/blog/engineering/the-good-and-the-bad-of-swift-programming-language/
https://uk.wikipedia.org/wiki/Swift_(%D0%BC%D0%BE%D0%B2%D0%B0_%D0%BF%D1%80%D0%BE%D0%B3%D1%80%D0%B0%D0%BC%D1%83%D0%B2%D0%B0%D0%BD%D0%BD%D1%8F)
https://en.wikipedia.org/wiki/Swift_(programming_language)
https://docs.swift.org/swift-book/
https://swift.org/about/
https://blackthorn-vision.com/blog/what-is-swift-programming-language-and-why-should-you-use-it
https://exyte.com/blog/introduciton-to-swift
https://www.itpro.co.uk/development/34417/what-is-the-swift-programming-language-and-why-should-i-learn-it
https://lenac1884.medium.com/what-is-the-swift-programming-language-b45e271175e2

如果有人能在我的代码上面给我建议，我将不胜感激:)