Last one ： I am here b Station learning python Basic learning 12 ： File operations
One 、 File backup
1、 step ：
Receive the file name entered by the user -> Plan the backup file name -> Backup file write data
2、 Code implementation ：
#1 Receive the target file name entered by the user
old_name = input(' Please enter the file name to be backed up :')
#2 Plan the backup file name
index = old_name.rfind('.') # Extract the subscript of the suffix point of the file
if index > 0:
postfix = old_name[index:] # Only valid files are backed up
new_name = old_name[:index] + '[ Backup ]' + postfix # Organize new file names
#3 Backup file write data
old_f = open(old_name,'rb')
new_f = open(new_name,'wb') # Open the source file and backup file
# Write source file data to backup file
while True:
con = old_f.read(1024)
if len(con) == 0:
break
new_f.write(con)
# Close file
old_f.close()
new_f.close()
Two 、 File operations
stay python The operation of files and folders in the os Module related functions
1、rename() rename
example ：os.rename(‘1.text’,‘10.text’)
Will file 1.text Rename it to 10.text
2、remove() Delete file
example ：os.remove(‘1.text’)
Delete 1.text file ( There is no mistake in the times )
3、 ... and 、 Folder operation
Same demand os modular
1、mkdir() Create folder
example ：os.mkdir(‘aa’)
Create folder aa（ The times have been wrong ）
2、rmdir() Delete folder
example ：os.rmdir(‘aa’)
Delete folder aa
3、getcwd() Return the directory path where the current folder is located
example ：print(os.getcwd())
Print the current file path
4、chdir() Change directory path
example ：os.chdir(‘aa’)
Change current path to folder aa Next
5、listdir（） Returns all files in a folder in the form of a list
example ：print（os.listdir(‘aa’)）
take aa All files in the folder , Return... As a list
6、1、rename() rename
example ：os.rename(‘aa’,‘bb’)
Put the folder aa Rename it to bb
Four 、 Simple application cases
Case study ： Batch modify file name , You can add and delete specified strings
import os
# Construct conditional data
flag = 1
# Find all the files
file_list = os.listdir()
# Construction name
for i in file_list:
if flag == 1:
new_name = 'python-' + i
elif flag == 2:
num = len('python-')
new_name = i[num:]
# rename
os.rename(i,new_name)
（flag=1, Perform prefix adding operation ,flag=2 Delete . Delete the runtime if any .idea The folder will report an error , You need to delete it before you can run ）
