python基礎之OS

#os

1. getcwd()

   #-*-coding:UTF-*-
   import os 
   print('文件所在的目錄爲%s:'%(os.getcwd()))
   # ./表示當前目錄
   print('當前目錄下的文件和目錄%s'%(os.listdir('./')))
   def powernum(power,*args):
       total=0
       for i in args:
           total+=pow(i,power)
       return total
   
   print (powernum(2,5))
   print (powernum(2,5,6))
   

2. demo-顯示所有視頻格式文件，mp4，avi，rmvb

   import os
   
   def search_file(start_dir, target) :
       os.chdir(start_dir)
       
       for each_file in os.listdir(os.curdir) :
           ext = os.path.splitext(each_file)[1]
           if ext in target :
               vedio_list.append(os.getcwd() + os.sep + each_file + os.linesep) 
           if os.path.isdir(each_file) :
               search_file(each_file, target) # 遞歸調用
               os.chdir(os.pardir) # 遞歸調用後切記返回上一層目錄
   
   start_dir = input('請輸入待查找的初始目錄：')
   program_dir = os.getcwd()
   
   target = ['.mp4', '.avi', '.rmvb']
   vedio_list = []
   
   search_file(start_dir, target)
   
   f = open(program_dir + os.sep + 'vedioList.txt', 'w')
   f.writelines(vedio_list)
   f.close()