11.1. pathlib — 面向对象的文件系统路径 ¶

11.1.2.1. 一般特性 ¶

路径不可变且可哈希。相同风味的路径可比较且可排序。这些特性遵守风味的大小写折叠语义：

>>> PurePosixPath('foo') == PurePosixPath('FOO')
False
>>> PureWindowsPath('foo') == PureWindowsPath('FOO')
True
>>> PureWindowsPath('FOO') in { PureWindowsPath('foo') }
True
>>> PureWindowsPath('C:') < PureWindowsPath('d:')
True
									

不同风味的路径比较不相等且无法排序：

>>> PureWindowsPath('foo') == PurePosixPath('foo')
False
>>> PureWindowsPath('foo') < PurePosixPath('foo')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: '<' not supported between instances of 'PureWindowsPath' and 'PurePosixPath'
									

11.1.2.2. 运算符 ¶

斜杠运算符帮助创建子级路径，类似于 os.path.join() :

>>> p = PurePath('/etc')
>>> p
PurePosixPath('/etc')
>>> p / 'init.d' / 'apache2'
PurePosixPath('/etc/init.d/apache2')
>>> q = PurePath('bin')
>>> '/usr' / q
PurePosixPath('/usr/bin')
									

路径对象可用于任何地方的对象实现 os.PathLike 被接受：

>>> import os
>>> p = PurePath('/etc')
>>> os.fspath(p)
'/etc'
									

路径的字符串表示是原生文件系统路径本身 (按本机形式，如在 Windows 采用反斜杠)，可以将其传递给任何按字符串接受文件路径的函数：

>>> p = PurePath('/etc')
>>> str(p)
'/etc'
>>> p = PureWindowsPath('c:/Program Files')
>>> str(p)
'c:\\Program Files'
									

同样，调用 bytes 在路径给出原生文件系统路径作为字节对象，编码通过 os.fsencode() :

>>> bytes(p)
b'/etc'
									

11.1.2.3. 访问单个部分 ¶

要访问路径的各个部分 (组件)，使用以下特性：

PurePath. parts ¶

给出访问路径各组件的元组：

>>> p = PurePath('/usr/bin/python3')
>>> p.parts
('/', 'usr', 'bin', 'python3')
>>> p = PureWindowsPath('c:/Program Files/PSF')
>>> p.parts
('c:\\', 'Program Files', 'PSF')
											

(注意，驱动和本地根是如何重新分组在一部分的)

11.1.2.4. 方法和特性 ¶

纯路径提供以下方法和特性：

PurePath. drive ¶

A string representing the drive letter or name, if any:

>>> PureWindowsPath('c:/Program Files/').drive
'c:'
>>> PureWindowsPath('/Program Files/').drive
''
>>> PurePosixPath('/etc').drive
''
											

UNC shares are also considered drives:

>>> PureWindowsPath('//host/share/foo.txt').drive
'\\\\host\\share'
											

PurePath. root ¶

A string representing the (local or global) root, if any:

>>> PureWindowsPath('c:/Program Files/').root
'\\'
>>> PureWindowsPath('c:Program Files/').root
''
>>> PurePosixPath('/etc').root
'/'
											

UNC shares always have a root:

>>> PureWindowsPath('//host/share').root
'\\'
											

PurePath. anchor ¶

The concatenation of the drive and root:

>>> PureWindowsPath('c:/Program Files/').anchor
'c:\\'
>>> PureWindowsPath('c:Program Files/').anchor
'c:'
>>> PurePosixPath('/etc').anchor
'/'
>>> PureWindowsPath('//host/share').anchor
'\\\\host\\share\\'
											

PurePath. parents ¶

An immutable sequence providing access to the logical ancestors of the path:

>>> p = PureWindowsPath('c:/foo/bar/setup.py')
>>> p.parents[0]
PureWindowsPath('c:/foo/bar')
>>> p.parents[1]
PureWindowsPath('c:/foo')
>>> p.parents[2]
PureWindowsPath('c:/')
											

PurePath. parent ¶

路径的逻辑父级：

>>> p = PurePosixPath('/a/b/c/d')
>>> p.parent
PurePosixPath('/a/b/c')
											

You cannot go past an anchor, or empty path:

>>> p = PurePosixPath('/')
>>> p.parent
PurePosixPath('/')
>>> p = PurePosixPath('.')
>>> p.parent
PurePosixPath('.')
											

注意

This is a purely lexical operation, hence the following behaviour:

>>> p = PurePosixPath('foo/..')
>>> p.parent
PurePosixPath('foo')
												

If you want to walk an arbitrary filesystem path upwards, it is recommended to first call Path.resolve() so as to resolve symlinks and eliminate “..” components.

PurePath. name ¶

A string representing the final path component, excluding the drive and root, if any:

>>> PurePosixPath('my/library/setup.py').name
'setup.py'
											

UNC drive names are not considered:

>>> PureWindowsPath('//some/share/setup.py').name
'setup.py'
>>> PureWindowsPath('//some/share').name
''
											

PurePath. suffix ¶

The file extension of the final component, if any:

>>> PurePosixPath('my/library/setup.py').suffix
'.py'
>>> PurePosixPath('my/library.tar.gz').suffix
'.gz'
>>> PurePosixPath('my/library').suffix
''
											

PurePath. suffixes ¶

A list of the path’s file extensions:

>>> PurePosixPath('my/library.tar.gar').suffixes
['.tar', '.gar']
>>> PurePosixPath('my/library.tar.gz').suffixes
['.tar', '.gz']
>>> PurePosixPath('my/library').suffixes
[]
											

PurePath. stem ¶

The final path component, without its suffix:

>>> PurePosixPath('my/library.tar.gz').stem
'library.tar'
>>> PurePosixPath('my/library.tar').stem
'library'
>>> PurePosixPath('my/library').stem
'library'
											

PurePath. as_posix ( ) ¶

Return a string representation of the path with forward slashes ( / ):

>>> p = PureWindowsPath('c:\\windows')
>>> str(p)
'c:\\windows'
>>> p.as_posix()
'c:/windows'
											

PurePath. as_uri ( ) ¶

将路径表示为 file URI. ValueError 被引发若不是绝对路径。

>>> p = PurePosixPath('/etc/passwd')
>>> p.as_uri()
'file:///etc/passwd'
>>> p = PureWindowsPath('c:/Windows')
>>> p.as_uri()
'file:///c:/Windows'
											

PurePath. is_absolute ( ) ¶

Return whether the path is absolute or not. A path is considered absolute if it has both a root and (if the flavour allows) a drive:

>>> PurePosixPath('/a/b').is_absolute()
True
>>> PurePosixPath('a/b').is_absolute()
False
>>> PureWindowsPath('c:/a/b').is_absolute()
True
>>> PureWindowsPath('/a/b').is_absolute()
False
>>> PureWindowsPath('c:').is_absolute()
False
>>> PureWindowsPath('//some/share').is_absolute()
True
											

PurePath. is_reserved ( ) ¶

With PureWindowsPath ，返回 True if the path is considered reserved under Windows, False otherwise. With PurePosixPath , False is always returned.

>>> PureWindowsPath('nul').is_reserved()
True
>>> PurePosixPath('nul').is_reserved()
False
											

File system calls on reserved paths can fail mysteriously or have unintended effects.

PurePath. joinpath ( *other ) ¶

Calling this method is equivalent to combining the path with each of the other arguments in turn:

>>> PurePosixPath('/etc').joinpath('passwd')
PurePosixPath('/etc/passwd')
>>> PurePosixPath('/etc').joinpath(PurePosixPath('passwd'))
PurePosixPath('/etc/passwd')
>>> PurePosixPath('/etc').joinpath('init.d', 'apache2')
PurePosixPath('/etc/init.d/apache2')
>>> PureWindowsPath('c:').joinpath('/Program Files')
PureWindowsPath('c:/Program Files')
											

PurePath. match ( pattern ) ¶

Match this path against the provided glob-style pattern. Return True if matching is successful, False 否则。

若 pattern is relative, the path can be either relative or absolute, and matching is done from the right:

>>> PurePath('a/b.py').match('*.py')
True
>>> PurePath('/a/b/c.py').match('b/*.py')
True
>>> PurePath('/a/b/c.py').match('a/*.py')
False
											

若 pattern is absolute, the path must be absolute, and the whole path must match:

>>> PurePath('/a.py').match('/*.py')
True
>>> PurePath('a/b.py').match('/*.py')
False
											

As with other methods, case-sensitivity is observed:

>>> PureWindowsPath('b.py').match('*.PY')
True
											

PurePath. relative_to ( *other ) ¶

Compute a version of this path relative to the path represented by other . If it’s impossible, ValueError is raised:

>>> p = PurePosixPath('/etc/passwd')
>>> p.relative_to('/')
PurePosixPath('etc/passwd')
>>> p.relative_to('/etc')
PurePosixPath('passwd')
>>> p.relative_to('/usr')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pathlib.py", line 694, in relative_to
    .format(str(self), str(formatted)))
ValueError: '/etc/passwd' does not start with '/usr'
											

PurePath. with_name ( name ) ¶

返回的新路径带 name changed. If the original path doesn’t have a name, ValueError is raised:

>>> p = PureWindowsPath('c:/Downloads/pathlib.tar.gz')
>>> p.with_name('setup.py')
PureWindowsPath('c:/Downloads/setup.py')
>>> p = PureWindowsPath('c:/')
>>> p.with_name('setup.py')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/antoine/cpython/default/Lib/pathlib.py", line 751, in with_name
    raise ValueError("%r has an empty name" % (self,))
ValueError: PureWindowsPath('c:/') has an empty name
											

PurePath. with_suffix ( suffix ) ¶

返回的新路径带 suffix changed. If the original path doesn’t have a suffix, the new suffix is appended instead. If the suffix is an empty string, the original suffix is removed:

>>> p = PureWindowsPath('c:/Downloads/pathlib.tar.gz')
>>> p.with_suffix('.bz2')
PureWindowsPath('c:/Downloads/pathlib.tar.bz2')
>>> p = PureWindowsPath('README')
>>> p.with_suffix('.txt')
PureWindowsPath('README.txt')
>>> p = PureWindowsPath('README.txt')
>>> p.with_suffix('')
PureWindowsPath('README')
											

11.1.3.1. 方法 ¶

Concrete paths provide the following methods in addition to pure paths methods. Many of these methods can raise an OSError if a system call fails (for example because the path doesn’t exist):

classmethod Path. cwd ( ) ¶

返回表示当前目录的新路径对象 (作为返回通过 os.getcwd() ):

>>> Path.cwd()
PosixPath('/home/antoine/pathlib')
											

classmethod Path. home ( ) ¶

返回表示用户主目录的新路径对象 (返回通过 os.path.expanduser() with ~ 构造)：

>>> Path.home()
PosixPath('/home/antoine')
											

3.5 版新增。

Path. stat ( ) ¶

返回此路径的有关信息 (类似于 os.stat() )。每次调用此方法时会查找结果。

>>> p = Path('setup.py')
>>> p.stat().st_size
956
>>> p.stat().st_mtime
1327883547.852554
											

Path. chmod ( mode ) ¶

更改文件模式和权限，像 os.chmod() :

>>> p = Path('setup.py')
>>> p.stat().st_mode
33277
>>> p.chmod(0o444)
>>> p.stat().st_mode
33060
											

Path. exists ( ) ¶

路径是否指向现有文件或目录：

>>> Path('.').exists()
True
>>> Path('setup.py').exists()
True
>>> Path('/etc').exists()
True
>>> Path('nonexistentfile').exists()
False
											

注意

If the path points to a symlink, exists() returns whether the symlink points to an existing file or directory.

Path. expanduser ( ) ¶

Return a new path with expanded ~ and ~user constructs, as returned by os.path.expanduser() :

>>> p = PosixPath('~/films/Monty Python')
>>> p.expanduser()
PosixPath('/home/eric/films/Monty Python')
											

3.5 版新增。

Path. glob ( pattern ) ¶

Glob the given pattern in the directory represented by this path, yielding all matching files (of any kind):

>>> sorted(Path('.').glob('*.py'))
[PosixPath('pathlib.py'), PosixPath('setup.py'), PosixPath('test_pathlib.py')]
>>> sorted(Path('.').glob('*/*.py'))
[PosixPath('docs/conf.py')]
											

The “ ** ” pattern means “this directory and all subdirectories, recursively”. In other words, it enables recursive globbing:

>>> sorted(Path('.').glob('**/*.py'))
[PosixPath('build/lib/pathlib.py'),
 PosixPath('docs/conf.py'),
 PosixPath('pathlib.py'),
 PosixPath('setup.py'),
 PosixPath('test_pathlib.py')]
											

注意

使用 “ ** ” pattern in large directory trees may consume an inordinate amount of time.

Path. group ( ) ¶

Return the name of the group owning the file. KeyError is raised if the file’s gid isn’t found in the system database.

Path. is_dir ( ) ¶

返回 True if the path points to a directory (or a symbolic link pointing to a directory), False if it points to another kind of file.

False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated.

Path. is_file ( ) ¶

返回 True if the path points to a regular file (or a symbolic link pointing to a regular file), False if it points to another kind of file.

False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated.

Path. is_symlink ( ) ¶

返回 True if the path points to a symbolic link, False 否则。

False is also returned if the path doesn’t exist; other errors (such as permission errors) are propagated.

Path. is_socket ( ) ¶

返回 True if the path points to a Unix socket (or a symbolic link pointing to a Unix socket), False if it points to another kind of file.

False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated.

Path. is_fifo ( ) ¶

返回 True if the path points to a FIFO (or a symbolic link pointing to a FIFO), False if it points to another kind of file.

False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated.

Path. is_block_device ( ) ¶

返回 True if the path points to a block device (or a symbolic link pointing to a block device), False if it points to another kind of file.

False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated.

Path. is_char_device ( ) ¶

返回 True if the path points to a character device (or a symbolic link pointing to a character device), False if it points to another kind of file.

False is also returned if the path doesn’t exist or is a broken symlink; other errors (such as permission errors) are propagated.

Path. iterdir ( ) ¶

When the path points to a directory, yield path objects of the directory contents:

>>> p = Path('docs')
>>> for child in p.iterdir(): child
...
PosixPath('docs/conf.py')
PosixPath('docs/_templates')
PosixPath('docs/make.bat')
PosixPath('docs/index.rst')
PosixPath('docs/_build')
PosixPath('docs/_static')
PosixPath('docs/Makefile')
											

Path. lchmod ( mode ) ¶

像 Path.chmod() but, if the path points to a symbolic link, the symbolic link’s mode is changed rather than its target’s.

Path. lstat ( ) ¶

像 Path.stat() but, if the path points to a symbolic link, return the symbolic link’s information rather than its target’s.

Path. mkdir ( mode=0o777 , parents=False , exist_ok=False ) ¶

Create a new directory at this given path. If mode is given, it is combined with the process’ umask value to determine the file mode and access flags. If the path already exists, FileExistsError 被引发。

若 parents is true, any missing parents of this path are created as needed; they are created with the default permissions without taking mode into account (mimicking the POSIX mkdir -p command).

若 parents is false (the default), a missing parent raises FileNotFoundError .

若 exist_ok is false (the default), FileExistsError is raised if the target directory already exists.

若 exist_ok is true, FileExistsError exceptions will be ignored (same behavior as the POSIX mkdir -p command), but only if the last path component is not an existing non-directory file.

3.5 版改变： exist_ok 参数被添加。

Path. open ( mode='r' , buffering=-1 , encoding=None , errors=None , newline=None ) ¶

Open the file pointed to by the path, like the built-in open() function does:

>>> p = Path('setup.py')
>>> with p.open() as f:
...     f.readline()
...
'#!/usr/bin/env python3\n'
											

Path. owner ( ) ¶

Return the name of the user owning the file. KeyError is raised if the file’s uid isn’t found in the system database.

Path. read_bytes ( ) ¶

Return the binary contents of the pointed-to file as a bytes object:

>>> p = Path('my_binary_file')
>>> p.write_bytes(b'Binary file contents')
20
>>> p.read_bytes()
b'Binary file contents'
											

3.5 版新增。

Path. read_text ( encoding=None , errors=None ) ¶

Return the decoded contents of the pointed-to file as a string:

>>> p = Path('my_text_file')
>>> p.write_text('Text file contents')
18
>>> p.read_text()
'Text file contents'
											

The file is opened and then closed. The optional parameters have the same meaning as in open() .

3.5 版新增。

Path. rename ( target ) ¶

Rename this file or directory to the given target . On Unix, if target exists and is a file, it will be replaced silently if the user has permission. target can be either a string or another path object:

>>> p = Path('foo')
>>> p.open('w').write('some text')
9
>>> target = Path('bar')
>>> p.rename(target)
>>> target.open().read()
'some text'
											

Path. replace ( target ) ¶

Rename this file or directory to the given target 。若 target points to an existing file or directory, it will be unconditionally replaced.

Path. resolve ( strict=False ) ¶

Make the path absolute, resolving any symlinks. A new path object is returned:

>>> p = Path()
>>> p
PosixPath('.')
>>> p.resolve()
PosixPath('/home/antoine/pathlib')
											

“ .. ” components are also eliminated (this is the only method to do so):

>>> p = Path('docs/../setup.py')
>>> p.resolve()
PosixPath('/home/antoine/pathlib/setup.py')
											

If the path doesn’t exist and strict is True , FileNotFoundError is raised. If strict is False , the path is resolved as far as possible and any remainder is appended without checking whether it exists. If an infinite loop is encountered along the resolution path, RuntimeError 被引发。

3.6 版新增： strict 自变量。

Path. rglob ( pattern ) ¶

This is like calling Path.glob() with “ ** ” added in front of the given pattern :

>>> sorted(Path().rglob("*.py"))
[PosixPath('build/lib/pathlib.py'),
 PosixPath('docs/conf.py'),
 PosixPath('pathlib.py'),
 PosixPath('setup.py'),
 PosixPath('test_pathlib.py')]
											

Path. rmdir ( ) ¶

Remove this directory. The directory must be empty.

Path. samefile ( other_path ) ¶

Return whether this path points to the same file as other_path , which can be either a Path object, or a string. The semantics are similar to os.path.samefile() and os.path.samestat() .

An OSError can be raised if either file cannot be accessed for some reason.

>>> p = Path('spam')
>>> q = Path('eggs')
>>> p.samefile(q)
False
>>> p.samefile('spam')
True
											

3.5 版新增。

Path. symlink_to ( target , target_is_directory=False ) ¶

Make this path a symbolic link to target . Under Windows, target_is_directory must be true (default False ) if the link’s target is a directory. Under POSIX, target_is_directory ’s value is ignored.

>>> p = Path('mylink')
>>> p.symlink_to('setup.py')
>>> p.resolve()
PosixPath('/home/antoine/pathlib/setup.py')
>>> p.stat().st_size
956
>>> p.lstat().st_size
8
											

注意

The order of arguments (link, target) is the reverse of os.symlink() ’s.

Path. touch ( mode=0o666 , exist_ok=True ) ¶

Create a file at this given path. If mode is given, it is combined with the process’ umask value to determine the file mode and access flags. If the file already exists, the function succeeds if exist_ok is true (and its modification time is updated to the current time), otherwise FileExistsError 被引发。

Path. unlink ( ) ¶

Remove this file or symbolic link. If the path points to a directory, use Path.rmdir() 代替。

Path. write_bytes ( data ) ¶

Open the file pointed to in bytes mode, write data to it, and close the file:

>>> p = Path('my_binary_file')
>>> p.write_bytes(b'Binary file contents')
20
>>> p.read_bytes()
b'Binary file contents'
											

An existing file of the same name is overwritten.

3.5 版新增。

Path. write_text ( data , encoding=None , errors=None ) ¶

Open the file pointed to in text mode, write data to it, and close the file:

>>> p = Path('my_text_file')
>>> p.write_text('Text file contents')
18
>>> p.read_text()
'Text file contents'
											

3.5 版新增。