Python| shutil.copy2() 方法

Python中的Shutil 模块提供了许多对文件和文件集合进行高级操作的功能。它属于 Python 的标准实用程序模块。该模块有助于自动复制和删除文件和目录的过程。
Python中的shutil.copy2()方法用于将源文件的内容复制到目标文件或目录。此方法与shutil.copy()方法相同，但它也尝试保留文件的元数据。
源必须表示文件，但目标可以是文件或目录。如果目标是目录，则文件将使用源中的基本文件名复制到目标。此外，目的地必须是可写的。如果目标是一个文件并且已经存在，那么它将被源文件替换，否则将创建一个新文件。

Syntax: shutil.copy2(source, destination, *, follow_symlinks = True)
Parameter: 
source: A string representing the path of the source file. 
destination: A string representing the path of the destination file or directory. 
follow_symlinks (optional) : The default value of this parameter is True. If it is False and source represents a symbolic link then it attempts to copy all metadata from the source symbolic link to the newly-created destination symbolic link. This functionality is platform dependent.
Note: The ‘*’ in parameter list indicates that all following parameters (Here in our case ‘follow_symlinks’) are keyword-only parameters and they can be provided using their name, not as positional parameter.
Return Type: This method returns a string which represents the path of newly created file. 
 

代码 #1：使用 shutil.copy2() 方法将文件从源复制到目标

Python3

# Python program to explain shutil.copy2() method
   
# importing os module
import os
 
# importing shutil module
import shutil
 
# path
path = '/home/User/Documents'
 
# List files and directories
# in '/home/User/Documents'
print("Before copying file:")
print(os.listdir(path))
 
 
# Source path
source = "/home/User/Documents/file.txt"
 
# Print the metadeta
# of source file
metadata = os.stat(source)
print("Metadata:", metadata, "\n")
 
# Destination path
destination = "/home/User/Documents/file(copy).txt"
 
# Copy the content of
# source to destination
dest = shutil.copy2(source, destination)
 
# List files and directories
# in "/home / User / Documents"
print("After copying file:")
print(os.listdir(path))
 
# Print the metadata
# of the destination file
matadata = os.stat(destination)
print("Metadata:", metadata)
 
# Print path of newly
# created file
print("Destination path:", dest)

输出：

Before copying file:
['hrithik.png', 'test.py', 'sample.txt', 'file.text', 'copy.cpp']
Metadata:  os.stat_result(st_mode=33188, st_ino=801113, st_dev=2056, st_nlink=1,
st_uid=1000, st_gid=1000, st_size=84, st_atime=1558866178, st_mtime=1558866156, 
st_ctime=1558866156) 

After copying file:
['hrithik.png', 'test.py', 'sample.txt', 'file.text', 'file(copy).txt', 'copy.cpp']
Metadata: os.stat_result(st_mode=33188, st_ino=801111, st_dev=2056, st_nlink=1,
st_uid=1000, st_gid=1000, st_size=84, st_atime=1558866178, st_mtime=1558866156,
st_ctime=1558933947)
Destination path: /home/User/Documents/file(copy).txt

代码 #2：如果目标是目录

Python3

# Python program to explain shutil.copy2() method
   
# importing os module
import os
 
# importing shutil module
import shutil
 
 
# Source path
source = "/home/User/Documents/file.txt"
 
# Destination path
destination = "/home/User/Desktop/"
 
# Copy the content of
# source to destination
dest = shutil.copy2(source, destination)
 
# List files and directories
# in "/home / User / Desktop"
print("After copying file:")
print(os.listdir(destination))
 
# Print path of newly
# created file
print("Destination path:", dest)

输出：

After copying file:
['input.txt', 'GeeksForGeeks', 'output.txt', 'file.txt', 'web.py', 'tree.cpp']
Destination path: /home/User/Desktop/file.txt

代码 #3：使用 shutil.copy2() 方法时可能出现的错误

Python3

# Python program to explain shutil.copy2() method
   
# importing shutil module
import shutil
 
 
# If the source and destination
# represents the same file
# 'SameFileError' exception
# will be raised
 
# If the destination is
# not writable
# 'PermissionError' exception
# will be raised
 
 
# Source path
source = "/home/User/Documents/file.txt"
 
# Destination path
destination = "/home/User/Documents/file.txt"
 
# Copy the content of
# source to destination
shutil.copy2(source, destination)

输出：

Traceback (most recent call last):
  File "try.py", line 26, in 
    dest = shutil.copy(source, destination)
  File "/usr/lib/python3.6/shutil.py", line 241, in copy2
    copyfile(src, dst, follow_symlinks=follow_symlinks)
  File "/usr/lib/python3.6/shutil.py", line 104, in copyfile
    raise SameFileError("{!r} and {!r} are the same file".format(src, dst))
shutil.SameFileError: '/home/User/Desktop/file.txt' and  '/home/User/Desktop/file.txt'
are the same file

代码 #4：使用 shutil.copy2() 方法时处理错误

Python3

# Python program to explain shutil.copy2() method
   
# importing shutil module
import shutil
 
# Source path
source = "/home/User/Documents/file.txt"
 
# Destination path
destination = "/home/User/Documents/file.txt"
 
# Copy the content of
# source to destination
 
try:
    shutil.copy2(source, destination)
    print("File copied successfully.")
 
# If source and destination are same
except shutil.SameFileError:
    print("Source and destination represents the same file.")
 
# If there is any permission issue
except PermissionError:
    print("Permission denied.")
 
# For other errors
except:
    print("Error occurred while copying file.")

输出：

Source and destination represents the same file.

参考： https://docs。 Python.org/3/library/shutil.html