random 模块
import random print(random.random())#(0,1)----float 大于0且小于1之间的小数 print(random.randint(1,3)) #[1,3] 大于等于1且小于等于3之间的整数 print(random.randrange(1,3)) #[1,3) 大于等于1且小于3之间的整数 print(random.choice([1,'23',[4,5]]))#1或者23或者[4,5] print(random.sample([1,'23',[4,5]],2))#列表元素任意2个组合 print(random.uniform(1,3))#大于1小于3的小数,如1.927109612082716 item=[1,3,5,7,9] random.shuffle(item) #打乱item的顺序,相当于"洗牌" print(item)
import random def make_code(n): res='' for i in range(n): s1=chr(random.randint(65,90)) s2=str(random.randint(0,9)) res+=random.choice([s1,s2]) return res print(make_code(9)) 生成随机验证码
shutil 模块 可以操作全新啊的处理文件模块
# 基于路径的文件复制: shutil.copyfile('source_file', 'target_file') # 基于流的文件复制: with open('source_file', 'rb') as r, open('target_file', 'wb') as w: shutil.copyfileobj(r, w) # 递归删除目标目录 shutil.rmtree('target_folder') # 文件移动 shutil.remove('old_file', 'new_file') # 文件夹压缩 shutil.make_archive('file_name', 'format', 'archive_path') # 文件夹解压 shutil.unpack_archive('unpack_file', 'unpack_name', 'format')
shelve 模块
shelve模块比pickle模块简单,只有一个open函数,返回类似字典的对象,可读可写;key必须为字符串,而值可以是python所支持的数据类型
# 将序列化文件操作dump与load进行封装
s_dic = shelve.open("target_file", writeback=True) # 注:writeback允许序列化的可变类型,可以直接修改值
# 序列化::存
s_dic['key1'] = 'value1'
s_dic['key2'] = 'value2'
# 反序列化:取
print(s_dic['key1'])
# 文件这样的释放
s_dic.close()
import shelve f=shelve.open(r'sheve.txt') # f['stu1_info']={'name':'egon','age':18,'hobby':['piao','smoking','drinking']} # f['stu2_info']={'name':'gangdan','age':53} # f['school_info']={'website':'http://www.pypy.org','city':'beijing'} print(f['stu1_info']['hobby']) f.close()
标准输入输出从错误流
import sys sys.stdout.write('msg') sys.stderr.write('msg') msg = sys.stdin.readline() # print默认是对sys.stdout.write('msg') + sys.stdout.write('\n')的封装 # 格式化结束符print:print('msg', end='')
xml xml文件操作模块
import xml.etree.ElementTree as ET # 读文件 tree = ET.parse("xmltest.xml") # 根节点 root_ele = tree.getroot() # 遍历下一级 for ele in root_ele: print(ele) # 全文搜索指定名的子标签 ele.iter("标签名") # 非全文查找满足条件的第一个子标签 ele.find("标签名") # 非全文查找满足条件的所有子标签 ele.findall("标签名") # 标签名 ele.tag # 标签内容 ele.text # 标签属性 ele.attrib # 修改 ele.tag = "新标签名" ele.text = "新文本" ele.set("属性名", "新属性值") # 删除 sup_ele.remove(sub_ele) # 添加 my_ele=ET.Element('myEle') my_ele.text = 'new_ele' my_ele.attrib = {'name': 'my_ele'} root.append(my_ele) # 重新写入硬盘 tree.write("xmltest.xml")
xml的格式如下,就是通过<>节点来区别数据结构的:
<?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> xml数据View Code
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:
# print(root.iter('year')) #全文搜索 # print(root.find('country')) #在root的子节点找,只找一个 # print(root.findall('country')) #在root的子节点找,找所有
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,child.attrib['name']) for i in child: print(i.tag,i.attrib,i.text) #只遍历year 节点 for node in root.iter('year'): print(node.tag,node.text) #--------------------------------------- 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') node.set('version','1.0') tree.write('test.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')View Code
#在country内添加(append)节点year2 import xml.etree.ElementTree as ET tree = ET.parse("a.xml") root=tree.getroot() for country in root.findall('country'): for year in country.findall('year'): if int(year.text) > 2000: year2=ET.Element('year2') year2.text='新年' year2.attrib={'update':'yes'} country.append(year2) #往country节点下添加子节点 tree.write('a.xml.swap')
自己创建xml文档:
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View Code