繁体   English   中英

用Nokogiri解析HTML字符串

[英]Parse HTML string with Nokogiri

我正在尝试编写一个ruby脚本,该脚本解析HTML字符串并从特定节点获取一些值。

目前,我正努力将字符串读入Nokogiri文档中:

这段代码:

#!/usr/bin/ruby

html_doc = Nokogiri::HTML("<html>  <meta content="text/html; charset=UTF-8"/>  <body style='margin:20px'>    <p>The following user has registered a device, click on the link below to review the user and make any changes if necessary.</p>    <ul style='list-style-type:none; margin:25px 15px;'>      <li><b>User name:</b> Test User</li>      <li><b>User email:</b> test@abc.com</li>      <li><b>Identifier:</b> abc123def132afd1213afas</li>      <li><b>Description:</b> Tom's iPad</li>      <li><b>Model:</b> iPad 3</li>      <li><b>Platform:</b> </li>      <li><b>App:</b> Test app name</li>      <li><b>UserID:</b> </li>     </ul>    <p>Review user: https://cirrus.app47.com/users?search=test@abc.com</p>            <hr style='height=2px; color:#aaa'/>        <p>We hope you enjoy the app store experience!</p>        <p style='font-size:18px; color:#999'>Powered by App47</p>      <img src='https://cirrus.app47.com/notifications/562506219ac25b1033000904/img' alt=''/></body></html>")

产生此错误:

$ ruby emailParser.rb 
emailParser.rb:3: syntax error, unexpected tIDENTIFIER, expecting ')'
...ML("<html>  <meta content="text/html; charset=UTF-8"/>  <bod...
...                               ^
emailParser.rb:3: syntax error, unexpected tSTRING_BEG, expecting end-of-input
...tent="text/html; charset=UTF-8"/>  <body style='margin:20px'...
...                               ^

请注意,我在这里尝试了具有相同结果的解决方案:

“语法错误,意外的tIDENTIFIER,期望$ end”

你必须HTML字符串引号从“ 里面的html为“求变字符串引号”改变。 这样的事情应该起作用:

#!/usr/bin/ruby

html_doc = Nokogiri::HTML('<html>  <meta content="text/html; charset=UTF-8"/>  <body style="margin:20px">    <p>The following user has registered a device, click on the link below to review the user and make any changes if necessary.</p>    <ul style="list-style-type:none; margin:25px 15px;">      <li><b>User name:</b> Test User</li>      <li><b>User email:</b> test@abc.com</li>      <li><b>Identifier:</b> abc123def132afd1213afas</li>      <li><b>Description:</b> Tom\'s iPad</li>      <li><b>Model:</b> iPad 3</li>      <li><b>Platform:</b> </li>      <li><b>App:</b> Test app name</li>      <li><b>UserID:</b> </li>     </ul>    <p>Review user: https://cirrus.app47.com/users?search=test@abc.com</p>            <hr style="height=2px; color:#aaa"/>        <p>We hope you enjoy the app store experience!</p>        <p style="font-size:18px; color:#999">Powered by App47</p>      <img src="https://cirrus.app47.com/notifications/562506219ac25b1033000904/img" alt=""/></body></html>')

问题是您的字符串中有双引号,这会使解析器感到困惑,因为您还使用了双引号将字符串引起来。 为了显示:

puts "foo"bar"
# => SyntaxError: unexpected tIDENTIFIER, expecting end-of-input
#    puts "foo"bar"
#                 ^

您可能打算打印foo"bar ,但是当解析器到达第二个" (在foo之后)时,它认为字符串已结束,因此它后面的内容会导致语法错误。 (Stack Overflow的语法高亮显示甚至给了您提示-查看第一行"foo"的颜色与bar"颜色不同吗?一个出色的语法高亮的文本编辑器将执行相同的操作。)

一种解决方案是改用单引号:

puts 'bar"baz'
# => bar"baz

在这种情况下,可以解决此问题,但实际上不会为您提供帮助,因为您的字符串中也包含单引号!

另一种解决方案是通过在\\前面加上引号来转义引号,如下所示:

puts "foo\"bar"
# => foo"bar

...但是对于像您这样的长字符串,这会有点乏味(有时会很棘手)。 更好的解决方案是使用一种特殊的字符串,称为“ heredoc”(对于“ here document”而言,其价值):

str = <<-END_OF_HTML
  <html>  <meta content="text/html; charset=UTF-8"/>  <body style='margin:20px'>    <p>The following user has registered a device, click on the link below to review the user and make any changes if necessary.</p>    <ul style='list-style-type:none; margin:25px 15px;'>      <li><b>User name:</b> Test User</li>      <li><b>User email:</b> test@abc.com</li>      <li><b>Identifier:</b> abc123def132afd1213afas</li>      <li><b>Description:</b> Tom's iPad</li>      <li><b>Model:</b> iPad 3</li>      <li><b>Platform:</b> </li>      <li><b>App:</b> Test app name</li>      <li><b>UserID:</b> </li>     </ul>    <p>Review user: https://cirrus.app47.com/users?search=test@abc.com</p>            <hr style='height=2px; color:#aaa'/>        <p>We hope you enjoy the app store experience!</p>        <p style='font-size:18px; color:#999'>Powered by App47</p>      <img src='https://cirrus.app47.com/notifications/562506219ac25b1033000904/img' alt=''/></body></html>
END_OF_HTML

html_doc = Nokogiri::HTML(str)

分隔符“ END_OF_HTML ”是任意的。 您可以使用EOFXYZZY或任何适合您的想法,尽管使用有意义的东西是一个好主意。 (您会注意到,Stack Overflow的语法突出显示在heredocs上有一些麻烦;不过,大多数代码编辑器对此都很好。)

您可以像这样使它紧凑一些:

Nokogiri::HTML <<-END_OF_HTML
  <html>  <meta content="text/html; charset=UTF-8"/>  <body style='margin:20px'>    <p>The following user has registered a device, click on the link below to review the user and make any changes if necessary.</p>    <ul style='list-style-type:none; margin:25px 15px;'>      <li><b>User name:</b> Test User</li>      <li><b>User email:</b> test@abc.com</li>      <li><b>Identifier:</b> abc123def132afd1213afas</li>      <li><b>Description:</b> Tom's iPad</li>      <li><b>Model:</b> iPad 3</li>      <li><b>Platform:</b> </li>      <li><b>App:</b> Test app name</li>      <li><b>UserID:</b> </li>     </ul>    <p>Review user: https://cirrus.app47.com/users?search=test@abc.com</p>            <hr style='height=2px; color:#aaa'/>        <p>We hope you enjoy the app store experience!</p>        <p style='font-size:18px; color:#999'>Powered by App47</p>      <img src='https://cirrus.app47.com/notifications/562506219ac25b1033000904/img' alt=''/></body></html>
END_OF_HTML

或带括号(看起来有些奇怪,但可以,有时是必需的):

Nokogiri::HTML(<<-END_OF_HTML)
  <html>  <meta content="text/html; charset=UTF-8"/>  <body style='margin:20px'>    <p>The following user has registered a device, click on the link below to review the user and make any changes if necessary.</p>    <ul style='list-style-type:none; margin:25px 15px;'>      <li><b>User name:</b> Test User</li>      <li><b>User email:</b> test@abc.com</li>      <li><b>Identifier:</b> abc123def132afd1213afas</li>      <li><b>Description:</b> Tom's iPad</li>      <li><b>Model:</b> iPad 3</li>      <li><b>Platform:</b> </li>      <li><b>App:</b> Test app name</li>      <li><b>UserID:</b> </li>     </ul>    <p>Review user: https://cirrus.app47.com/users?search=test@abc.com</p>            <hr style='height=2px; color:#aaa'/>        <p>We hope you enjoy the app store experience!</p>        <p style='font-size:18px; color:#999'>Powered by App47</p>      <img src='https://cirrus.app47.com/notifications/562506219ac25b1033000904/img' alt=''/></body></html>
END_OF_HTML

您可以在Ruby文档的“ 文字”部分中阅读有关heredocs以及其他表示字符串的其他方式的信息。

暂无
暂无

声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM