[TOC] ## 前言說明 xml是實現不同語言或程序之間進行數據交換的協議，跟json功能差不多，但要復雜和麻煩一些,是json誕生之前大多數程序的統一接口協議 ## xml格式舉例 xml的格式如下，就是通過<>節點來區別數據結構的: ``` <?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> ``` ## python中的xml協議 xml協議在各個語言里的都是支持的，在python中用`xml.etree.ElementTree`模塊操作xml ### 導入模塊遍歷 ``` import xml.etree.ElementTree as ET tree = ET.parse("xmltest.xml") root = tree.getroot() print(root.tag) #遍歷xml文檔 for child in root: print(child.tag, child.attrib) for i in child: print(i.tag,i.text) #只遍歷year 節點 for node in root.iter('year'): print(node.tag,node.text) ``` 修改和刪除xml文檔內容 ~~~ 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") #刪除node for country in root.findall('country'): rank = int(country.find('rank').text) if rank > 50: root.remove(country) tree.write('output.xml') ~~~ 自己創建xml文檔 ~~~ 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) #生成文檔對象 et.write("test.xml", encoding="utf-8",xml_declaration=True) ET.dump(new_xml) #打印生成的格式 ~~~