python的正则替换,re.sub

import re
a = 'sadf.4.555.asdf.123sadf.sadf'
b = re.sub(r"\.([0-9a-zA-Z]+)\.[0-9a-zA-Z]+$", "-你好啊时间-\g<1>", a)

2, 批量修改文件

#_*_ encoding: utf-8 _*_   @author: ty  heris
#项目名称:   pycharm_file 会自动替换为当前项目名称
#创建时间:  2018/5/8 会自动替换为当前日期

# '''
# 'ORDER BY对查询结果排序.avi'
# >>> re.search('(\d-\d+)',i2)+re.sub('-(\d-\d+)','',i2)
# Traceback (most recent call last):
#   File "<stdin>", line 1, in <module>
# TypeError: unsupported operand type(s) for +: 're.Match' and 'str'
# >>> re.search('(\d-\d+)',i2).group(1)+re.sub('-(\d-\d+)','',i2)
# '8-34ORDER BY对查询结果排序.avi'
# >>> re.search('(\d-\d+)',i2).group(1)+re.sub('-(\d-\d+)','',i2)
# '8-34ORDER BY对查询结果排序.avi'
# >>>
# '''
import os, re
path = "E:/go_learn_video/麦子学院招牌课程[明星python编程视频VIP教程]/06-之mysql基础/"    # 目标路径
# path = "Y:/pythons3/day01/"    # 目标路径
"""os.listdir(path) 操作效果为 返回指定路径(path)文件夹中所有文件名"""
# filename_list =   # 扫描目标路径的文件,将文件名存入列表

for i in os.listdir(path):
    try:
        print(i)
        # i1 = re.search("(day.*?)\.",i).group(1)
        # print('++',f'<span class="page-num">(P\d+)</span><span class="part">{i}</span>')
        # a = f'<span class="page-num">(P\d+)</span><span class="part">.*?{i1}</span>'
        # reg = re.compile(a)
        # print('2222', i1,a)
        # a2 = re.search(a,fhtml).group(1)
        # a2 = re.search('<span class="page-num">(P\d+)</span><span class="part">{i}</span>', i).group(1)
        # print('--',a2,type(a2) )  # ORDER BY对查询结果排序-8-34.avi
        # new_name = re.sub("\d+",a2 ,i)
        # a = 'sadf.4.555.asdf.123sadf.sadf'
        # new_name = re.sub(r"-(\d-\d+)", "\g<1>", i)
        new_name = re.sub(r"(.+)-(\d-\d+)", "\g<2>_\g<1>", i)
        print(new_name)
        os.rename(path + i, path + new_name)

        print(new_name,"ok")
        # os.rename(path +  '/' + i, path +  '/' + new_name)
    except Exception as e :
        print(new_name,e)


# with open('C:\\Users\\Administrator.USER-20190427VG\\Desktop\\c.html',encoding='utf-8') as f1:
#     fhtml = f1.read()
    # print('内容:',fhtml)


    # re.search('<span class="page-num">(P\d+)</span><span class="part">(.*)</span>', i).group(2)


    # print(i)
    # used_name = path + filename_list[a]
    # new_name = "_".join(re.findall(".*?-0(\d+).*_(.*)", test_str))
#     print(used_name,)
#     new_name = path + "new_" + filename_list[a]
#     os.rename(used_name,new_name)
    # print("文件%s重命名成功,新的文件名为%s" %(used_name,new_name))
    # a += 1



# for j in filename_list:
#     print('这个是j',j)
#     try :
#         print(os.path.join(path,j))
#         for i in os.listdir(os.path.join(path,j)):
#             try:
#                 print('++',i)
#                 new_name = re.sub("\spytho.*?-",'-',i)
#                 # print(path + j +'/'+ i,'福建省大反馈', path +j +'/'+  new_name)
#                 # print('---------',os.path.join(os.path.join(path,j),i))
#                 os.rename(path +j +'/'+  i, path +j +'/'+  new_name)
#             except Exception :
#                 pass
#     except Exception:
#         pass



# <li class=""><a href="/video/BV1Ly4y1C7Ni?p=30" class="router-link-active" title="05-GO语言开发-day4-数组">
#     <div class="link-content">
#         <i class="van-icon-videodetails_play" style="display: none;"></i>
#         <span class="page-num">P30</span>
#         <span class="part">05-GO语言开发-day4-数组</span>
#     </div>
#     <div class="duration">28:59</div>
# </a></li>