我正在尝试使用Nokogiri解析HTML字符串,但是我遇到了一些递归问题,我不知道为什么。
给定这些命令:
string = <h3>Lancers were arranged. </h3>
<div>Gabriel found himself partnered with Miss Ivors.</div>
<br>She leaned. He lit a <b>candle</b>.
They followed him in silence, their feet falling in soft thuds on the thickly carpeted stairs.<br>
body = Nokogiri::HTML(string)
result = []
body.traverse { |node| result << node }
我希望有上述元素的数组。相反,我得到了这个:
[#<Nokogiri::XML::DTD:0x3fde1f3d5274 name="html">
#<Nokogiri::XML::Text:0x3fde1e88d330 "Lancers were arranged. ">
#<Nokogiri::XML::Element:0x3fde1ea56a68 name="h3" children=[#<Nokogiri::XML::Text:0x3fde1e88d330 "Lancers were arranged. ">]>
#<Nokogiri::XML::Text:0x3fde1e88c764 "Gabriel found himself partnered with Miss Ivors.">
#<Nokogiri::XML::Element:0x3fde1e88cd04 name="div" children=[#<Nokogiri::XML::Text:0x3fde1e88c764 "Gabriel found himself partnered with Miss Ivors.">]>
#<Nokogiri::XML::Element:0x3fde1e88c0fc name="br">
#<Nokogiri::XML::Text:0x3fde1e88b9e0 "She leaned. He lit a ">
#<Nokogiri::XML::Text:0x3fde1eba6c60 "candle">
#<Nokogiri::XML::Element:0x3fde1e88b5f8 name="b" children=[#<Nokogiri::XML::Text:0x3fde1eba6c60 "candle">]>
#<Nokogiri::XML::Text:0x3fde1eba6454 ". They followed him in silence
their feet falling in soft thuds on the thickly carpeted stairs.">
#<Nokogiri::XML::Element:0x3fde1eba5f54 name="br">
#<Nokogiri::XML::Element:0x3fde1ea56f7c name="body" children=[#<Nokogiri::XML::Element:0x3fde1ea56a68 name="h3" children=[#<Nokogiri::XML::Text:0x3fde1e88d330 "Lancers were arranged. ">]>
#<Nokogiri::XML::Element:0x3fde1e88cd04 name="div" children=[#<Nokogiri::XML::Text:0x3fde1e88c764 "Gabriel found himself partnered with Miss Ivors.">]>
#<Nokogiri::XML::Element:0x3fde1e88c0fc name="br">
#<Nokogiri::XML::Text:0x3fde1e88b9e0 "She leaned. He lit a ">
#<Nokogiri::XML::Element:0x3fde1e88b5f8 name="b" children=[#<Nokogiri::XML::Text:0x3fde1eba6c60 "candle">]>
#<Nokogiri::XML::Text:0x3fde1eba6454 ". They followed him in silence
their feet falling in soft thuds on the thickly carpeted stairs.">
#<Nokogiri::XML::Element:0x3fde1eba5f54 name="br">]>
#<Nokogiri::XML::Element:0x3fde1ea575e4 name="html" children=[#<Nokogiri::XML::Element:0x3fde1ea56f7c name="body" children=[#<Nokogiri::XML::Element:0x3fde1ea56a68 name="h3" children=[#<Nokogiri::XML::Text:0x3fde1e88d330 "Lancers were arranged. ">]>
#<Nokogiri::XML::Element:0x3fde1e88cd04 name="div" children=[#<Nokogiri::XML::Text:0x3fde1e88c764 "Gabriel found himself partnered with Miss Ivors.">]>
#<Nokogiri::XML::Element:0x3fde1e88c0fc name="br">
#<Nokogiri::XML::Text:0x3fde1e88b9e0 "She leaned. He lit a ">
#<Nokogiri::XML::Element:0x3fde1e88b5f8 name="b" children=[#<Nokogiri::XML::Text:0x3fde1eba6c60 "candle">]>
#<Nokogiri::XML::Text:0x3fde1eba6454 ". They followed him in silence
their feet falling in soft thuds on the thickly carpeted stairs.">
#<Nokogiri::XML::Element:0x3fde1eba5f54 name="br">]>]>
#<Nokogiri::HTML::Document:0x3fde1f3d6084 name="document" children=[#<Nokogiri::XML::DTD:0x3fde1f3d5274 name="html">
#<Nokogiri::XML::Element:0x3fde1ea575e4 name="html" children=[#<Nokogiri::XML::Element:0x3fde1ea56f7c name="body" children=[#<Nokogiri::XML::Element:0x3fde1ea56a68 name="h3" children=[#<Nokogiri::XML::Text:0x3fde1e88d330 "Lancers were arranged. ">]>
#<Nokogiri::XML::Element:0x3fde1e88cd04 name="div" children=[#<Nokogiri::XML::Text:0x3fde1e88c764 "Gabriel found himself partnered with Miss Ivors.">]>
#<Nokogiri::XML::Element:0x3fde1e88c0fc name="br">
#<Nokogiri::XML::Text:0x3fde1e88b9e0 "She leaned. He lit a ">
#<Nokogiri::XML::Element:0x3fde1e88b5f8 name="b" children=[#<Nokogiri::XML::Text:0x3fde1eba6c60 "candle">]>
#<Nokogiri::XML::Text:0x3fde1eba6454 ". They followed him in silence
their feet falling in soft thuds on the thickly carpeted stairs.">
#<Nokogiri::XML::Element:0x3fde1eba5f54 name="br">]>]>]>]
对不起,长度。谁能帮我弄清楚为什么会这样?和/或如何预防它?
发生这种情况是因为traverse
递归地调用提供的块及其所有子块。因此,它将 html 字符串的每个节点添加到 result
数组中,而不仅仅是顶级节点。您看到的"多重结果"是Nokogiri节点定义inspect
的结果。例如,返回数组中的第三个元素表示h3
节点,但也打印其所有子节点,其中包括作为数组第 2 个元素的text
节点。
如果您希望result
包含对文档中每个节点的引用,那么这是正确的方法。如果您只想使用顶级节点,请使用children
当你解析不完整的html时,Nokogiri会自动添加doctype和html和body元素。您必须像这样解析它以避免此行为:
body = Nokogiri::HTML::DocumentFragment.parse(your_html)
如果您希望结果是和不包括文本节点的元素数组,您可以这样做:
result = body.xpath('./*')
然后结果(为清楚起见转换为字符串)将是:
["<h3>Lancers were arranged. </h3>",
"<div>Gabriel found himself partnered with Miss Ivors.</div>",
"<br>",
"<b>candle</b>",
"<br>"]