How to get the attributes of an XML tag using Ruby with REXML?

问题

I want to output an xml file in a specific way only using REXML with Ruby. Here is what the xml file looks like:

<desc>
     <id>2408</id>
     <who name="Joe Silva">joe@silva.com</who>
     <when>Today</when>
     <thetext>Hello World</thetext>
</desc>
<desc>
     <id>2409</id>
     <who name="Joe Silva2">joe2@silva.com</who>
     <when>Future</when>
     <thetext>Hello World Again</thetext>
</desc>

So far, here is the code I use:

document.elements.each("//desc") {
    |e| e.elements.each 
        |i| puts "#{i.name} : #{i.text}"
    puts "\n"
}

This gives me the following output:

commentid : 2408
who : joe@silva.com
bug_when : Today
thetext : Hello World

commentid : 2409
who : joe2@silva.com
bug_when : Future
thetext : Hello World Again

I can access each tag's text but not their attributes. How do I get access to the attributes and get an output with the name attribute?

So the output I want is:

commentid : 2408
name : Joe Silva
who : joe@silva.com
bug_when : Today
thetext : Hello World

Let me know if further explanation is required.

回答1:

I wouldn't use REXML, but instead would use Nokogiri. Using that, I'd write something like:

require 'nokogiri'

doc = Nokogiri::XML(<<EOT)
<xml>
<desc>
     <id>2408</id>
     <who name="Joe Silva">joe@silva.com</who>
     <when>Today</when>
     <thetext>Hello World</thetext>
</desc>
<desc>
     <id>2409</id>
     <who name="Joe Silva2">joe2@silva.com</who>
     <when>Future</when>
     <thetext>Hello World Again</thetext>
</desc>
</xml>
EOT

data = doc.search('desc').map{ |desc|
  desc.children.reject(&:text?).map { |desc_child|
    [desc_child.name, desc_child.text]
  }.to_h
}

data
# => [{"id"=>"2408",
#      "who"=>"joe@silva.com",
#      "when"=>"Today",
#      "thetext"=>"Hello World"},
#     {"id"=>"2409",
#      "who"=>"joe2@silva.com",
#      "when"=>"Future",
#      "thetext"=>"Hello World Again"}]

That provides an array of hashes containing the node names and their text.

How to change the name of the nodes to be used as keys and print it out is left for you to figure out.

来源：https://stackoverflow.com/questions/28157224/how-to-get-the-attributes-of-an-xml-tag-using-ruby-with-rexml

标签

ruby

xml

scripting

rexml