python xml
xml是实现不同语言或程序之间进行数据交换的协议,跟json差不多,但json使用起来更简单,不过,古时候,在json还没诞生的黑暗年代,大家只能选择用xml呀,至今很多传统公司如金融行业的很多系统的接口还主要是xml。
xml的格式如下,就是通过<>节点来区别数据结构的:
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<? xml version="1.0"?> < data > < country name="Liechtenstein"> < rank updated="yes">2</ rank > < year >2008</ year > < gdppc >141100</ gdppc > < neighbor name="Austria" direction="E"/> < neighbor name="Switzerland" direction="W"/> </ country > < country name="Singapore"> < rank updated="yes">5</ rank > < year >2011</ year > < gdppc >59900</ gdppc > < neighbor name="Malaysia" direction="N"/> </ country > < country name="Panama"> < rank updated="yes">69</ rank > < year >2011</ year > < gdppc >13600</ gdppc > < neighbor name="Costa Rica" direction="W"/> < neighbor name="Colombia" direction="E"/> </ country > </ data > |
xml协议在各个语言里的都 是支持的,在python中可以用以下模块操作xml
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import xml.etree.ElementTree as ET tree = ET.parse("xmltest.xml") root = tree.getroot() print(root.tag) #遍历xml文档 for child in root: print(child.tag, child.attrib) for i in child: print(i.tag,i.text) #只遍历year 节点 for node in root.iter('year'): print(node.tag,node.text) |
修改和删除xml文档内容
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import xml.etree.ElementTree as ET tree = ET.parse("xmltest.xml") root = tree.getroot() #修改 for node in root.iter('year'): new_year = int(node.text) + 1 node.text = str(new_year) node.set("updated","yes") tree.write("xmltest.xml") #删除node for country in root.findall('country'): rank = int(country.find('rank').text) if rank > 50: root.remove(country) tree.write('output.xml') |
自己创建xml文档
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import xml.etree.ElementTree as ET new_xml = ET.Element("namelist") name = ET.SubElement(new_xml,"name",attrib={"enrolled":"yes"}) age = ET.SubElement(name,"age",attrib={"checked":"no"}) sex = ET.SubElement(name,"sex") sex.text = '33' name2 = ET.SubElement(new_xml,"name",attrib={"enrolled":"no"}) age = ET.SubElement(name2,"age") age.text = '19' et = ET.ElementTree(new_xml) #生成文档对象 et.write("test.xml", encoding="utf-8",xml_declaration=True) ET.dump(new_xml) #打印生成的格式 |