Question

这可能是一个简单的问题，但我对python和编程一般都是新手。

我正在开发一个简单的程序，用于在镜像源位置的目录结构的同时将.mp3文件从一个位置复制/移动到另一个位置。到目前为止我的工作，但它也在目标位置创建新的文件夹，即使源文件夹不包含mp3文件。我只想创建新目录，如果源包含.mp3s，否则它可能会导致目标中的一堆空文件夹。

这是我到目前为止所做的：

import os
import shutil #Used for copying files

##CONFIG
source_dir = "C:\Users\username\Desktop\iTunes\\" #set the root folder that you want to     scan and move files from.  This script will scan recursively.
destPath = "C:\Users\username\Desktop\converted From iTunes" #set the destination root that you want to move files to.  Any non-existing sub directories will be created.
ext = ".mp3" #set the type of file you want to search for.
count = 0 #initialize counter variable to count number of files moved
##

##FIND FILES
for dirName, subdirList, fileList in os.walk(source_dir):

    #set the path for the destination folder(s)
    dest = destPath + dirName.replace(source_dir, '\\') 

    #if the source directory doesn't exist in the destination folder
    #then create a new folder
    if not os.path.isdir(dest):
        os.mkdir(dest)
        print('Directory created at: ' + dest)

    for fname in fileList:
        if fname.endswith(ext) :
            #determine source & new file locations
            oldLoc = dirName + '\\' + fname
            newLoc = dest + '\\' + fname

            if os.path.isfile(newLoc): # check to see if the file already exists.  If it does print out a message saying so.
                print ('file "' + newLoc + fname + '" already exists')

            if not os.path.isfile(newLoc): #if the file doesnt exist then copy it and print out confirmation that is was copied/moved
                try:
                    shutil.move(oldLoc, newLoc)
                    print('File ' + fname + ' copied.')
                    count = count + 1
                except IOError:
                    print('There was an error copying the file:  "' + fname + '"')
                    print 'error'            

print "\n"
print str(count) + " files were moved."
print "\n"

所以如果文件夹结构类似于：

root->
 band 1->
  album name->
   song.m4a,
   song2.m4a

现在它将在目标driectory中创建所有这些文件夹，即使没有.mp3s可以复制.....

感谢任何帮助！

Answer 1

我想我会为这类事情创建自己的副本包装：

def fcopy(src,dest):
    """
    Copy file from source to dest.  dest can include an absolute or relative path
    If the path doesn't exist, it gets created
    """
    dest_dir = os.path.dirname(dest)
    try:
        os.makedirs(dest_dir)
    except os.error as e:
        pass #Assume it exists.  This could fail if you don't have permissions, etc...
    shutil.copy(src,dest)

现在，您可以在任何.mp3文件上遍历调用此函数的树。

Answer 2

shutils.copytree会不会在更少的行中执行您想要的操作吗？

Answer 3

我能想到的最简单的事情就是让现有的代码只是让它跳过任何没有任何.mp3文件的文件夹。这可以通过将以下项和if语句添加到循环顶部来轻松完成。 itertools.ifilter()和fnmatch.fnmatch()函数可以一起使用，以简化对具有适当扩展名的文件的检查。

from itertools import ifilter
from fnmatch import fnmatch

ext = '.mp3'
fnPattern = '*'+ext

for dirName, subdirList, fileList in os.walk(source_dir):
    if not any(ifilter(lambda fname: fnmatch(fname, fnPattern), fileList)):
        print '  skipping "{}"'.format(dirName)
        continue
    ...

您还必须将代码中的os.mkdir(dest)更改为os.makedirs(dest)，以确保在需要将文件复制到相应的文件时创建先前迭代跳过的所有子目录目标目录的子分支。

您可以通过创建和保存具有扩展名的匹配文件的可能空迭代器来稍微优化一些事情，然后稍后再次使用它来确定要复制的文件：

from itertools import ifilter
from fnmatch import fnmatch

ext = '.mp3'
fnPattern = '*'+ext

for dirName, subdirList, fileList in os.walk(source_dir):

    # generate list of files in directory with desired extension
    matches = ifilter(lambda fname: fnmatch(fname, fnPattern), fileList)

    # skip subdirectory if it does not contain any files of interest
    if not matches:
        continue
    ...
    ... create destination directory with os.makedirs()
    ...
    #  copy each file to destination directory
    for fname in matches:
      ... copy file

如果python中的某些文件类型，则移动文件并创建目录

3 个答案: