如何在Python中更改目錄（cd）？

像在shell命令中同樣cd來更改工做目錄。

如何在Python中更改當前的工做目錄？

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#1樓

這是上下文管理器更改工做目錄的示例。 它比其餘地方提到的ActiveState版本要簡單，但這能夠完成工做。

上下文管理器： cd

import os

class cd:
    """Context manager for changing the current working directory"""
    def __init__(self, newPath):
        self.newPath = os.path.expanduser(newPath)

    def __enter__(self):
        self.savedPath = os.getcwd()
        os.chdir(self.newPath)

    def __exit__(self, etype, value, traceback):
        os.chdir(self.savedPath)

或者使用ContextManager嘗試更簡潔的等效方法（以下） 。

例

import subprocess # just to call an arbitrary command e.g. 'ls'

# enter the directory like this:
with cd("~/Library"):
   # we are in ~/Library
   subprocess.call("ls")

# outside the context manager we are back wherever we started.

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#2樓

正如其餘人已經指出的那樣，以上全部解決方案僅會更改當前進程的工做目錄。 當您返回Unix shell時，這將丟失。 若是不顧一切，您能夠使用如下可怕的方法在Unix上更改父shell目錄：

def quote_against_shell_expansion(s):
    import pipes
    return pipes.quote(s)

def put_text_back_into_terminal_input_buffer(text):
    # use of this means that it only works in an interactive session
    # (and if the user types while it runs they could insert characters between the characters in 'text'!)
    import fcntl, termios
    for c in text:
        fcntl.ioctl(1, termios.TIOCSTI, c)

def change_parent_process_directory(dest):
    # the horror
    put_text_back_into_terminal_input_buffer("cd "+quote_against_shell_expansion(dest)+"\n")

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#3樓

進一步進入方向指出了由Brian和基於SH （1.0.8+）

from sh import cd, ls

cd('/tmp')
print ls()

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#4樓

cd()易於使用生成器和裝飾器編寫。

from contextlib import contextmanager
import os

@contextmanager
def cd(newdir):
    prevdir = os.getcwd()
    os.chdir(os.path.expanduser(newdir))
    try:
        yield
    finally:
        os.chdir(prevdir)

而後，即便在引起異常以後，也將還原目錄：

os.chdir('/home')

with cd('/tmp'):
    # ...
    raise Exception("There's no place like home.")
# Directory is now back to '/home'.

---

#5樓

更改腳本過程的當前目錄很簡單。 我認爲問題其實是如何更改從中調用python腳本的命令窗口的當前目錄，這很是困難。 Windows中的Bat腳本或Bash shell中的Bash腳本可使用普通的cd命令來執行此操做，由於shell自己就是解釋器。 在Windows和Linux中，Python都是程序，沒有程序能夠直接更改其父級的環境。 可是，將簡單的Shell腳本與Python腳本結合使用可完成大多數艱苦的工做，便可達到預期的效果。 例如，爲了製做一個具備遍歷歷史記錄的擴展cd命令以進行向後/向前/選擇從新訪問，我編寫了一個由簡單的bat腳本調用的相對複雜的Python腳本。 遍歷列表存儲在文件中，目標目錄位於第一行。 當python腳本返回時，bat腳本讀取文件的第一行並將其做爲cd的參數。 完整的蝙蝠腳本（爲簡潔起見，減去註釋）爲：

if _%1 == _. goto cdDone
if _%1 == _? goto help
if /i _%1 NEQ _-H goto doCd
:help
echo d.bat and dSup.py 2016.03.05. Extended chdir.
echo -C = clear traversal list.
echo -B or nothing = backward (to previous dir).
echo -F or - = forward (to next dir).
echo -R = remove current from list and return to previous.
echo -S = select from list.
echo -H, -h, ? = help.
echo . = make window title current directory.
echo Anything else = target directory.
goto done

:doCd
%~dp0dSup.py %1
for /F %%d in ( %~dp0dSupList ) do (
    cd %%d
    if errorlevel 1 ( %~dp0dSup.py -R )
    goto cdDone
)
:cdDone
title %CD%
:done

python腳本dSup.py是：

import sys, os, msvcrt

def indexNoCase ( slist, s ) :
    for idx in range( len( slist )) :
        if slist[idx].upper() == s.upper() :
            return idx
    raise ValueError

# .........main process ...................
if len( sys.argv ) < 2 :
    cmd = 1 # No argument defaults to -B, the most common operation
elif sys.argv[1][0] == '-':
    if len(sys.argv[1]) == 1 :
        cmd = 2 # '-' alone defaults to -F, second most common operation.
    else :
        cmd = 'CBFRS'.find( sys.argv[1][1:2].upper())
else :
    cmd = -1
    dir = os.path.abspath( sys.argv[1] ) + '\n'

# cmd is -1 = path, 0 = C, 1 = B, 2 = F, 3 = R, 4 = S

fo = open( os.path.dirname( sys.argv[0] ) + '\\dSupList', mode = 'a+t' )
fo.seek( 0 )
dlist = fo.readlines( -1 )
if len( dlist ) == 0 :
    dlist.append( os.getcwd() + '\n' ) # Prime new directory list with current.

if cmd == 1 : # B: move backward, i.e. to previous
    target = dlist.pop(0)
    dlist.append( target )
elif cmd == 2 : # F: move forward, i.e. to next
    target = dlist.pop( len( dlist ) - 1 )
    dlist.insert( 0, target )
elif cmd == 3 : # R: remove current from list. This forces cd to previous, a
                # desireable side-effect
    dlist.pop( 0 )
elif cmd == 4 : # S: select from list
# The current directory (dlist[0]) is included essentially as ESC.
    for idx in range( len( dlist )) :
        print( '(' + str( idx ) + ')', dlist[ idx ][:-1])
    while True :
        inp = msvcrt.getche()
        if inp.isdigit() :
            inp = int( inp )
            if inp < len( dlist ) :
                print( '' ) # Print the newline we didn't get from getche.
                break
        print( ' is out of range' )
# Select 0 means the current directory and the list is not changed. Otherwise
# the selected directory is moved to the top of the list. This can be done by
# either rotating the whole list until the selection is at the head or pop it
# and insert it to 0. It isn't obvious which would be better for the user but
# since pop-insert is simpler, it is used.
    if inp > 0 :
        dlist.insert( 0, dlist.pop( inp ))

elif cmd == -1 : # -1: dir is the requested new directory.
# If it is already in the list then remove it before inserting it at the head.
# This takes care of both the common case of it having been recently visited
# and the less common case of user mistakenly requesting current, in which
# case it is already at the head. Deleting and putting it back is a trivial
# inefficiency.
    try:
        dlist.pop( indexNoCase( dlist, dir ))
    except ValueError :
        pass
    dlist = dlist[:9] # Control list length by removing older dirs (should be
                      # no more than one).
    dlist.insert( 0, dir ) 

fo.truncate( 0 )
if cmd != 0 : # C: clear the list
    fo.writelines( dlist )

fo.close()
exit(0)