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lxml是python中处理xml的一个非常强大的库，可以非常方便的解析和生成xml文件。下面的内容翻译了链接中的一部分

 

1.生成空xml节点

from lxml import etreeroot = etree.Element("root")print(etree.tostring(root, pretty_print=True))

2.生成xml子节点

from lxml import etreeroot = etree.Element("root")root.append(etree.Element("child1"))     #方法一child2 = etree.SubElement(root, "child2")  #方法二child2 = etree.SubElement(root, "child3")print(etree.tostring(root))

3.生成带内容的xml节点

from lxml import etreeroot = etree.Element("root")root.text = "Hello World"print(etree.tostring(root, pretty_print=True))

     
      Hello World
     

4.属性

lxml中将属性以字典的形式存储

生成属性

from lxml import etreeroot = etree.Element("root", intersting = "totally")  #方法一root.set("hello","huhu")  #方法二root.text = "Hello World"print(etree.tostring(root))

     
      Hello World
     

获取属性

方法一：

root.get("interesting")root.get("hello")

totallyhuhu

方法二：

attributes = root.attribprint(attributes["interesting"])

遍历属性

for name, value in sorted(root.items()):     print('%s = %r' % (name, value))

5.生成特殊内容

如下xml，中间的文字被<br/>分割，需要用到.tail

Hello
World

html = etree.Element("html")body = etree.SubElement(html, "body")body.text = "TEXT"br = etree.SubElement(body, "br")br.tail = "TAIL"etree.tostring(html)

6.遍历

遍历节点

for element in root.iter():     print("%s - %s" % (element.tag, element.text))

遍历指定子节点，将子节点名写入iter()

for element in root.iter("child"):     print("%s - %s" % (element.tag, element.text))

7.用XPath查找节点内容

build_text_list = etree.XPath("//text()") # lxml.etree only!print(build_text_list(html))

8.查找节点

iterfind():遍历所有节点匹配表达式

findall():返回满足匹配的节点列表

find():返回满足匹配的第一个

findtext():返回第一个满足匹配条件的.text内容

设有以下xml内容

root = etree.XML("
     
      aText
       
     ")

查找子节点

>>> print(root.find("b"))None>>> print(root.find("a").tag)a

查找树中任意节点

>>> print(root.find(".//b").tag)b>>> [ b.tag for b in root.iterfind(".//b") ]['b', 'b']

查找具有指定属性的节点

>>> print(root.findall(".//a[@x]")[0].tag)a>>> print(root.findall(".//a[@y]"))[]

9.字符串解析为XML

>>> some_xml_data = "
     
      data
     ">>> root = etree.fromstring(some_xml_data)>>> print(root.tag)root>>> etree.tostring(root)b'
     
      data
     '

10.使用E-factory快速生成XML和HTML

>>> from lxml.builder import E>>> def CLASS(*args): # class is a reserved word in Python        return {
   "class":' '.join(args)}>>> html = page = (    E.html(       # create an Element called "html"      E.head(        E.title("This is a sample document")      ),      E.body(        E.h1("Hello!", CLASS("title")),        E.p("This is a paragraph with ", E.b("bold"), " text in it!"),        E.p("This is another paragraph, with a", "\n      ",          E.a("link", href="http://www.python.org"), "."),        E.p("Here are some reservered characters: 
     
      ."),        etree.XML("
      
And finally an embedded XHTML fragment.
"),      )    )  )>>> print(etree.tostring(page, pretty_print=True))      
              
      
Hello!
    
      
This is a paragraph with bold text in it!
    
      
This is another paragraph, with a      link.
    
      
Here are some reservered characters: <spam&egg>.
    
      
And finally an embedded XHTML fragment.