快速解析html的最佳实践是什么？

一尘不染

快速解析html的最佳实践是什么？

html

我是Swift新手。我需要类似SwiftiOS项目中Python的BeautifulSoup之类的东西。准确地说，我需要将所有这些都href以<a>结尾".txt"。我应该采取什么步骤？

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2020-05-10

共1个答案

一尘不染

有几个不错的 HTML解析 库，它们使用Swift，Objective-C如下所示：

hpple
NDHpple
Kanna( old Swift-HTML-Parser)
Fuzi
SwiftSoup
Ji

看一下上面发布的四个库中的以下示例，这些示例主要是使用XPath 2.0进行解析的：

hpple ：

let data = NSData(contentsOfFile: path)
let doc = TFHpple(htmlData: data)

if let elements = doc.searchWithXPathQuery("//a/@href[ends-with(.,'.txt')]") as? [TFHppleElement] {
   for element in elements {
       println(element.content)
   }
}

NDHpple ：

let data = NSData(contentsOfFile: path)!
let html = NSString(data: data, encoding: NSUTF8StringEncoding)!
let doc = NDHpple(HTMLData: html)
if let elements = doc.searchWithXPathQuery("//a/@href[ends-with(.,'.txt')]") {
   for element in elements {
     println(element.children?.first?.content)
   }
}

Kanna (Xpath and CSS Selectors):

let html = "<html><head></head><body><ul><li><input type='image' name='input1' value='string1value' class='abc' /></li><li><input type='image' name='input2' value='string2value' class='def' /></li></ul><span class='spantext'><b>Hello World 1</b></span><span class='spantext'><b>Hello World 2</b></span><a href='example.com'>example(English)</a><a href='example.co.jp'>example(JP)</a></body>"

if let doc = Kanna.HTML(html: html, encoding: NSUTF8StringEncoding) {
   var bodyNode   = doc.body

   if let inputNodes = bodyNode?.xpath("//a/@href[ends-with(.,'.txt')]") {
      for node in inputNodes {
         println(node.contents)
      }
   }
}

Fuzi（Xpath and CSS Selectors） ：

let html = "<html><head></head><body><ul><li><input type='image' name='input1' value='string1value' class='abc' /></li><li><input type='image' name='input2' value='string2value' class='def' /></li></ul><span class='spantext'><b>Hello World 1</b></span><span class='spantext'><b>Hello World 2</b></span><a href='example.com'>example(English)</a><a href='example.co.jp'>example(JP)</a></body>"

do {
  // if encoding is omitted, it defaults to NSUTF8StringEncoding
  let doc = try HTMLDocument(string: html, encoding: NSUTF8StringEncoding)

  // XPath queries
  for anchor in doc.xpath("//a/@href[ends-with(.,'.txt')]") {
    print(anchor.stringValue)
  }

} catch let error {
    print(error)
}

该ends-with功能是Xpath 2.0的一部分。

SwiftSoup（CSS Selectors） ：

do{
    let doc: Document = try SwiftSoup.parse("...")
    let links: Elements = try doc.select("a[href]") // a with href
    let pngs: Elements = try doc.select("img[src$=.png]")

    // img with src ending .png
    let masthead: Element? = try doc.select("div.masthead").first()

    // div with class=masthead
    let resultLinks: Elements? = try doc.select("h3.r > a") // direct a after h3
} catch Exception.Error(let type, let message){
    print(message)
} catch {
   print("error")
}

Ji（XPath） ：

let jiDoc = Ji(htmlURL: URL(string: "http://www.apple.com/support")!)
let titleNode = jiDoc?.xPath("//head/title")?.first
print("title: \(titleNode?.content)") // title: Optional("Official Apple Support")

我希望这可以帮助你。

2020-05-10