Python - 获取目录中具有大小的文件列表

在本文中，我们将看到如何提取目录的文件列表及其大小。为此，我们将使用 OS 模块。

Python的OS 模块提供了与操作系统交互的功能。操作系统属于 Python 的标准实用程序模块。该模块提供了一种使用操作系统相关功能的可移植方式。 os.path 模块是Python中 OS 模块的子模块，用于通用路径名操作。

使用的功能

• Python的os.path.isfile()方法用于检查指定路径是否为现有的常规文件。

Syntax: os.path.isfile(path)

Parameter:  

• path:  path-like object representing a file system path. A path-like object is either a string or bytes object representing a path.

Return Type: This method returns a Boolean value of class bool. This method returns True if specified path is an existing regular file, otherwise returns False. 

• Python的os.path.join()方法智能地连接一个或多个路径组件。此方法连接各种路径组件，并在每个非空部分（最后一个路径组件除外）之后使用一个目录分隔符 ('/')。如果要加入的最后一个路径组件为空，则在末尾放置一个目录分隔符 ('/')。如果路径组件表示绝对路径，则所有先前加入的组件都将被丢弃，并从绝对路径组件继续加入。

Syntax: os.path.join(path, *paths)  

Parameter:  

• path:  A path-like object representing a file system path.  
• *path: A path-like object representing a file system path. It represents the path components to be joined.
• A path-like object is either a string or bytes object representing a path.
• Note: The special syntax *args (here *paths) in function definitions in python is used to pass a variable number of arguments to
• a function.

Return Type: This method returns a string which represents the concatenated path components.  

• os.listdir():这个 Python的方法用于获取指定目录下所有文件和目录的列表。如果我们不指定任何目录，则将返回当前工作目录中的文件和目录列表。

Syntax: os.listdir(path)

Parameters:  

• path (optional) : path of the directory

Return Type: This method returns the list of all files and directories in the specified path. The return type of this method is list.

• 筛选（）： 这个 方法在一个函数的帮助下过滤给定的序列，该函数测试序列中的每个元素是否为真。

Syntax: filter(function, sequence)

Parameters:

• function: function that tests if each element of a sequence true or not.
• sequence: sequence which needs to be filtered, it can be sets, lists, tuples, or containers of any iterators.

Returns: returns an iterator that is already filtered.

• os.stat() : Python的这个方法在指定的路径上执行 stat() 系统调用。该方法用于获取指定路径的状态。

Syntax: os.stat(path)

Parameter:

path: A string or bytes object representing a valid path

Returns : st_size: It represents the size of the file in bytes.

• os.walk() :这个 通过自顶向下或自底向上遍历树，在目录树中生成文件名。对于以目录 top 为根的树中的每个目录（包括 top 本身），它产生一个 3 元组（dirpath、dirnames、filenames）。

具有大小的目录中的文件列表

在这部分代码中，我们将只获取文件名称和大小的列表。在这段代码中，我们有 os.stat()函数来获取每个文件的大小，大小将导致 'byte' 所以我们必须将文件的大小从 1024*1024 中除以得到 '兆字节”以便更好地理解。

使用的目录

Python3

# import python modules
import os
 
# directory name from which
# we are going to extract our files with its size
path = "D:\Books"
 
# Get list of all files only in the given directory
fun = lambda x : os.path.isfile(os.path.join(path,x))
files_list = filter(fun, os.listdir(path))
 
# Create a list of files in directory along with the size
size_of_file = [
    (f,os.stat(os.path.join(path, f)).st_size)
    for f in files_list
]
# Iterate over list of files along with size
# and print them one by one.
for f,s in size_of_file:
    print("{} : {}mb".format(f, round(s/(1024*1024),3)))

输出：

2015_Book_LinearAlgebraDoneRight.pdf : 2.199mb
An Introduction to Statistical Learning - Gareth James.pdf : 8.996mb
Hand-on-ML.pdf : 7.201mb
ISLR Seventh Printing.pdf : 11.375mb
The Business of the 21st Century - Robert Kiyosaki.pdf : 8.932mb
The Elements of Statistical Learning - Trevor Hastie.pdf : 12.687mb
the_compound_effect_ebook.pdf : 5.142mb

按大小排序的目录中的文件路径列表

在前面的代码中，我们只输出了文件名及其对应的大小，但在这种情况下，我们打印了文件路径而不是每个文件名，并根据每个文件名的大小升序对其进行了排序。在这种情况下，我们必须使用 sorted函数，根据文件大小对文件进行排序。

Syntax: sorted(iterable, key=key, reverse=reverse)

Parameters:

• iterable : The sequence to sort, list, dictionary, tuple etc.
• key : A Function to execute to decide the order. Default is None

reverse : A Boolean. False will sort ascending, True will sort descending. Default is False

使用的目录

蟒蛇3

# import python modules
import os
 
# directory name from which we are
# going to extract our files with its size
path = "D:\ABC"
 
# Get list of all files only in the given directory
fun = lambda x : os.path.isfile(os.path.join(path,x))
 
files_list = filter(fun, os.listdir(path))
 
# Create a list of files in directory along with the size
size_of_file = [
    (f,os.stat(os.path.join(path, f)).st_size)
    for f in files_list
]
# Iterate over list of files along with size
# and print them one by one.
# now we have print the result by
# sorting the size of the file
# so, we have call sorted function
# to sort according to the size of the file
 
# created a lambda function that help us
# to sort according the size of the file.
fun = lambda x : x[1]
 
 
# in this case we have its file path instead of file
for f,s in sorted(size_of_file,key = fun):
    print("{} : {}mb".format(os.path.join(path,f),round(s/(1024*1024),3)))

输出：

D:\ABC\1.png : 0.022mb
D:\ABC\17.png : 0.024mb
D:\ABC\16.png : 0.036mb
D:\ABC\15.png : 0.047mb
D:\ABC\7.png : 0.074mb
D:\ABC\10.png : 0.076mb
D:\ABC\6.png : 0.09mb
D:\ABC\13.png : 0.093mb
D:\ABC\14.png : 0.097mb
D:\ABC\8.png : 0.104mb
D:\ABC\2.png : 0.115mb
D:\ABC\5.png : 0.126mb
D:\ABC\11.mp4 : 5.966mb

目录中按大小排序的文件名列表：

这段代码与之前的代码没有太大的不同，这段代码有一个很小的变化，在这段代码中，我们只是将输出打印为文件名而不是文件路径，其余代码相同。

使用的目录

蟒蛇3

# import python modules
import os
 
# directory name from which we are
# going to extract our files with its size
path = "D:\ABC"
 
# Get list of all files only in the given directory
fun = lambda x : os.path.isfile(os.path.join(path,x))
 
files_list = filter(fun, os.listdir(path))
 
# Create a list of files
# in directory along with the size
size_of_file = [
    (f,os.stat(os.path.join(path, f)).st_size)
    for f in files_list
]
# Iterate over list of files along with size
# and print them one by one.
# now we have print the result by
# sorting the size of the file
# so, we have call sorted function
# to sort according to the size of the file
 
# created a lambda function that help
# us to sort according the size of the file.
fun = lambda x : x[1]
 
# in this case we have use its file name.
for f,s in sorted(size_of_file,key = fun):
    print("{} : {}mb".format(f,round(s/(1024*1024),3)))

输出：

1.png : 0.022mb
17.png : 0.024mb
16.png : 0.036mb
15.png : 0.047mb
7.png : 0.074mb
10.png : 0.076mb
6.png : 0.09mb
13.png : 0.093mb
14.png : 0.097mb
8.png : 0.104mb
2.png : 0.115mb
5.png : 0.126mb
11.mp4 : 5.966mb

按大小排序的目录和子目录中的文件路径列表：

这段代码不同于以上所有 3 段代码，在这段代码中，我们必须显示所有子目录和文件大小及其名称或文件路径。因此，首先，我们必须使用os.walk()函数获取目录中存在的所有 sub_directores 和文件，这会生成一个包含 3 项内容的生成器对象，即路径、子目录名称和文件名。给定目录。然后我们创建了一个具有大小的文件列表，接下来，我们必须获取目录中存在的 sub_directory 的大小。最后，我们输出了我们的代码，其中包含文件名及其子目录的排序大小。

Syntax: os.walk(path)

Parameters:

path : The path of the directory from where we can create our directory tree.

Returns : 

• root : Prints out directories only from what you specified.
• dirs : Prints out sub-directories from root.
• files : Prints out all files from root and directories.

使用的目录

蟒蛇3

# import python modules
import os
 
# directory name from which we are
# going to extract our files with its size
path = "D:\ABC"
 
# get the path p, sub_directory sub_dir,
# and filename files from the given path
walk_method = os.walk(path)
 
# using exception handling to remove
# the stop iteration from generator object
# which we get the output from os.walk()  method.
while True:
    try:
        p, sub_dir, files = next(walk_method)
        break
    except:
        break 
         
# Create a list of files in directory along with the size
size_of_file = [
    (f,os.stat(os.path.join(path, f)).st_size)
    for f in files
]
  
# get the size of the sub_dir of the given path
for sub in sub_dir:
    i = os.path.join(path,sub)
    size = 0
    for k in os.listdir(i):
        size += os.stat(os.path.join(i,k)).st_size
    size_of_file.append((sub,size))
     
# Iterate over list of files along with size
# and print them one by one.
# now we have print the result by
# sorting the size of the file
# so, we have call sorted function
# to sort according to the size of the file
 
# in this case we have use its file paths.
for f,s in sorted(size_of_file,key = lambda x : x[1]):
    print("{} : {}mb".format(os.path.join(path,f),round(s/(1024*1024),3)))

输出：

D:\ABC\1.png : 0.022mb
D:\ABC\17.png : 0.024mb
D:\ABC\16.png : 0.036mb
D:\ABC\15.png : 0.047mb
D:\ABC\7.png : 0.074mb
D:\ABC\10.png : 0.076mb
D:\ABC\6.png : 0.09mb
D:\ABC\13.png : 0.093mb
D:\ABC\14.png : 0.097mb
D:\ABC\8.png : 0.104mb
D:\ABC\2.png : 0.115mb
D:\ABC\5.png : 0.126mb
D:\ABC\11.mp4 : 5.966mb
D:\ABC\Books : 56.532mb