代码驿站移动版

当前位置：主页 > 软件编程 > Python代码 >

Python中的pathlib库使用详解

时间：2022-12-05 12:53:27 | 栏目：Python代码 | 点击：次

1. pathlib库介绍

相比常用的 os.path 而言，pathlib 对于目录路径的操作更简洁也更贴近 Pythonic（Python代码风格的）。但是它不单纯是为了简化操作，还有更大的用途。

pathlib 是Python内置库，Python 文档给它的定义是：

The pathlib module – object-oriented filesystem paths(面向对象的文件系统路径)

pathlib 提供表示文件系统路径的类，其语义适用于不同的操作系统。

2. pathlib库下Path类的基本使用

2.1 获取文件名

from pathlib import Path  # 导入pathlib的Path类
import os
path = "/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb"
p = Path(path)
print(f"获取文件名：{p.name}")  # 获取文件名：pathlib库的使用.ipynb

2.2 获取文件前缀和后缀

—— .stem & .suffix

from pathlib import Path
import os
path = "/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb"
p = Path(path)
print(f"获取前缀：{p.stem}")  # 获取前缀：pathlib库的使用
print(f"获取后缀：{p.suffix}")  # 获取后缀：.ipynb

2.3 获取文件的文件夹及上一级、上上级文件夹

—— .parent

from pathlib import Path
import os
path = "/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb"
p = Path(path)
print(f"获取当前文件所属文件夹：{p.parent}")
print(f"获取上一级文件夹：{p.parent.parent}")
print(f"获取上上一级文件夹：{p.parent.parent.parent}")
"""
获取当前文件所属文件夹：/home/leovin/JupyterNotebookFolders
获取上一级文件夹：/home/leovin
获取上上一级文件夹：/home
"""

Note: 最上级的文件夹是一个/

2.4 获取该文件所属的文件夹及其父文件夹

—— .parents

from pathlib import Path
import os
path = "/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb"
p = Path(path)
print(f"获取当前文件所属文件夹及其父文件夹：{p.parents}\n")
# 遍历
for idx, folder_path in enumerate(p.parents):
    print(f"No.{idx}: {folder_path}")
"""
获取当前文件所属文件夹及其父文件夹：<PosixPath.parents>

No.0: /home/leovin/JupyterNotebookFolders
No.1: /home/leovin
No.2: /home
No.3: /
"""

2.5 文件绝对路径

按照/进行分割 —— .parts

from pathlib import Path
import os
path = "/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb"
p = Path(path)
print(f"将文件的绝对路径按照`/`进行分割，返回一个tuple：{p.parts}\n")
# 遍历
for idx, element in enumerate(p.parts):
    print(f"No.{idx}: {element}")
"""
获取当前文件所属文件夹及其父文件夹：<PosixPath.parents>
No.0: /
No.1: home
No.2: leovin
No.3: JupyterNotebookFolders
No.4: pathlib库的使用.ipynb
"""

2.6 获取当前工作目录

—— Path.cwd()

from pathlib import Path
import os
path_1 = Path.cwd()
path_2 = os.getcwd()
print(f"Path.cwd(): {path_1}")
print(f"os.getcwd(): {path_2}")
"""
Path.cwd(): /home/leovin/JupyterNotebookFolders
os.getcwd(): /home/leovin/JupyterNotebookFolders
"""

2.7 获取用户

home目录路径 —— Path.home()系列

from pathlib import Path
print(f"获取用户home路径: {Path.home()}")
"""
获取用户home路径: /home/leovin
"""

2.8 获取文件详细信息

—— object.stat()

from pathlib import Path
p = Path("/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb")
print(f"获取文件详细信息: {p.stat()}\n")
print(f"获取文件字节大小: {p.stat().st_size}\n")
print(f"获取文件创建时间: {p.stat().st_ctime}\n")  # c: create
print(f"获取文件上次修改时间: {p.stat().st_mtime}\n")  # m:: modify
"""
获取文件详细信息: os.stat_result(st_mode=33204, st_ino=23860358, st_dev=2052, st_nlink=1, st_uid=1000, st_gid=1000, st_size=12125, st_atime=1653039478, st_mtime=1653039478, st_ctime=1653039478)

获取文件字节大小: 12125

获取文件创建时间: 1653039478.703161

获取文件上次修改时间: 1653039478.703161
"""

可以看到，object.stat().xxx就是在调用attr 

2.9 检查目录或者文件是否存在

—— Path("路径").exists()

from pathlib import Path
print(f"目标路径的文件是否存在: {Path('/home/leovin/JupyterNotebookFolders/xxx').exists()}")  # False
print(f"目标路径的文件是否存在: {Path('/home/leovin/JupyterNotebookFolders').exists()}")  # True

2.10 检查指定指定路径是否为folder或者file

—— Path("路径").is_file() & Path("路径").is_dir()

from pathlib import Path
print(f"目标路径是否为文件: {Path('/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb').is_file()}")  # True
print(f"目标路径是否为文件夹: {Path('/home/leovin/JupyterNotebookFolders/').is_dir()}")  # True

directory为文件夹

2.11 将相对路径转换为绝对路径

—— Path("路径").resolve()

from pathlib import Path
print(f"目标路径是否为文件: {Path('/home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb').is_file()}")  # True
print(f"目标路径是否为文件夹: {Path('/home/leovin/JupyterNotebookFolders/').is_dir()}")  # True

2.12 遍历一个目录

—— Path("路径").iterdir()

from pathlib import Path
path_object = Path("/home/leovin/JupyterNotebookFolders/").iterdir()
print(f"path_object: {path_object}")  # path_object: <generator object Path.iterdir at 0x7f0ca0061c10>
# 迭代目录对象
for idx, element in enumerate(path_object):
    print(f"No.{idx}: {element}")
"""
path_object: <generator object Path.iterdir at 0x7f0ca0061c10>
No.0: /home/leovin/JupyterNotebookFolders/temp
No.1: /home/leovin/JupyterNotebookFolders/torch.meshgrid().ipynb
No.2: /home/leovin/JupyterNotebookFolders/array.argsort().ipynb
No.3: /home/leovin/JupyterNotebookFolders/切片....ipynb
No.4: /home/leovin/JupyterNotebookFolders/logging信息.log
No.5: /home/leovin/JupyterNotebookFolders/Python中类的私有变量、私有方法、静态方法.ipynb
No.6: /home/leovin/JupyterNotebookFolders/temp_file.ipynb
No.7: /home/leovin/JupyterNotebookFolders/example.log
No.8: /home/leovin/JupyterNotebookFolders/Python语法.ipynb
No.9: /home/leovin/JupyterNotebookFolders/.ipynb_checkpoints
No.10: /home/leovin/JupyterNotebookFolders/craw.data.txt
No.11: /home/leovin/JupyterNotebookFolders/test.txt
No.12: /home/leovin/JupyterNotebookFolders/logging的学习.ipynb
No.13: /home/leovin/JupyterNotebookFolders/Test.ipynb
No.14: /home/leovin/JupyterNotebookFolders/算法题
No.15: /home/leovin/JupyterNotebookFolders/functions.ipynb
No.16: /home/leovin/JupyterNotebookFolders/mask转0&1.ipynb
No.17: /home/leovin/JupyterNotebookFolders/Multi_Task_in_Python.ipynb
No.18: /home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb
No.19: /home/leovin/JupyterNotebookFolders/三种激活函数绘制.ipynb
"""

2.13 获取所有符合pattern的文件

—— Path("路径").glob("folder1/xxx.格式")

from pathlib import Path
pattern = "JupyterNotebookFolders/*.ipynb"
glob_generator = Path("/home/leovin/").glob(pattern)
# 遍历返回的对象 -> 返回的是绝对路径
for idx, element in enumerate(glob_generator):
    print(f"No.{idx}: {element}")
"""
No.0: /home/leovin/JupyterNotebookFolders/torch.meshgrid().ipynb
No.1: /home/leovin/JupyterNotebookFolders/array.argsort().ipynb
No.2: /home/leovin/JupyterNotebookFolders/切片....ipynb
No.3: /home/leovin/JupyterNotebookFolders/Python中类的私有变量、私有方法、静态方法.ipynb
No.4: /home/leovin/JupyterNotebookFolders/temp_file.ipynb
No.5: /home/leovin/JupyterNotebookFolders/Python语法.ipynb
No.6: /home/leovin/JupyterNotebookFolders/logging的学习.ipynb
No.7: /home/leovin/JupyterNotebookFolders/Test.ipynb
No.8: /home/leovin/JupyterNotebookFolders/functions.ipynb
No.9: /home/leovin/JupyterNotebookFolders/mask转0&1.ipynb
No.10: /home/leovin/JupyterNotebookFolders/Multi_Task_in_Python.ipynb
No.11: /home/leovin/JupyterNotebookFolders/pathlib库的使用.ipynb
No.12: /home/leovin/JupyterNotebookFolders/三种激活函数绘制.ipynb
"""

2.14 删除文件（非目录）

—— Path("路径").unlink()

from pathlib import Path
# 当前文件夹下的txt文件
for idx, element in enumerate(Path("./").glob("*.txt")):
    print(f"No.{idx}: {element}")
print("-" * 30)
"""
    删除指定的文件（非目录）
        1. 是真的删除而非unlink
        2. 如果文件不存在则保存
"""
try:
    Path("./will_be_deleted.txt").unlink()
except Exception as e:
    print(f"删除文件发生错误，原因为: {e}")
# 当前文件夹下的txt文件
for idx, element in enumerate(Path("./").glob("*.txt")):
    print(f"No.{idx}: {element}")
"""
No.0: will_be_deleted.txt
No.1: craw.data.txt
No.2: test.txt
------------------------------
No.0: craw.data.txt
No.1: test.txt

报错的输出：
No.0: craw.data.txt
No.1: test.txt
------------------------------
删除文件发生错误，原因为: [Errno 2] No such file or directory: 'will_be_deleted.txt'
No.0: craw.data.txt
No.1: test.txt
"""

3. pathlib库与os库的对比

os库 pathlib库 描述 英文说明
os.path.abspath(("文件路径")) Path("文件路径").resolve() 将路径转换为绝对路径 -
os.chmod() Path("文件路径").chmod(xxx) 更改文件权限 change mode
os.mkdir(("文件路径")) Path("文件路径").mkdir() 新建文件夹 make directory
os.rename("文件路径", "xxx") Path("文件路径").rename("xxx") 重命名文件/文件夹名称 -
os.replace(a, b) Path("文件路径").replace(a, b) 替换字符串 -
os.rmdir() Path("文件路径").rmdir() 删除文件夹（里面必须是空的） remove directory
os.remove("文件路径") / os.unlink("文件路径") Path("文件路径").unlink() 删除文件（非目录） -
os.getcwd() Path("文件路径").cwd() 获取当前文件工作目录 current work directory
os.path.isdir() Path("文件路径").is_dir() 判断当前路径是否为目录 -
os.path.isfile() Path("文件路径").is_file() 判断当前路径是否为文件 -
os.stat() Path("文件路径").stat() 返回当前路径的信息 status
os.path.isabs() Path("文件路径").is_absolute() 判断当前路径是否为绝对路径 -
os.path.basename() Path("文件路径").name 返回文件/目录的基础名称（不带路径） -
os.path.dirname() Path("文件路径").parent 返回路径所属文件夹名称 -
os.path.samefile() Path("文件路径").samefile(xxx) 判断两个文件是否相同 -
os.path.splitext("文件路径") (Path("文件路径").stem, Path("文件路径").suffix) 将文件名分离，分成前缀和后缀 stem + suffix

参考

https://www.jb51.net/article/193402.htm

https://docs.python.org/zh-cn/3/library/pathlib.html?highlight=pathlib#module-pathlib

您可能感兴趣的文章:

相关文章