将路径名写入文件 (Python)

Question

我正在处理大量图像并尝试搜索 jpeg，然后将它们的路径写入文件。目前，我可以找到我想要的所有 jpeg。但是，我的“索引”文件中的每个新路径都会覆盖最后一个。因此，它根本不是一个索引/列表，而是一个包含 a/path/to/just/one/file.jpg 的文本文件我简化了我的代码并在下面添加了它。它很冗长，但这是为了我的阅读利益以及其他像我这样的新手。#----------#-->Import Modules#I'm pretty sure there is redundancy here and it's not well laid out#but I'm new to coding and it worksimport osimport pathlibimport glob, osfrom pathlib import Pathimport os.pathfrom os import path#----------#-->Global Vars#Simplified example of my variablesworking_dir = "/Users/myname/path/to/working dir"records_dir = str(working_dir + "/Records")#----------#-->Search Location#Define where the jpeg search is to take place#(actually dictated via user input, Minecraft is just an example)search_locations = ["/Users/myname/minecraft"]#---------#--> Search for jpgs and write their paths to a file#define the file where the jpeg paths are to be stored,#(I'm referring to the storage file as an index of sorts)jpg_index = str(records_dir + "/index_for_all_jpgs")#Its embedded in a forloop because the user can add multiple locationsfor search_location in search_locations:    #get the desired paths from the search location    for path in Path(search_location).rglob('*.jpg'):        #Open the index where paths are to be stored        with open(jpg_index, 'w') as filehandle:            #This is supposed to write each paths as a new line            #But it doesn't work            filehandle.writelines('%s\n' % path)我也尝试过使用更简单的想法；filehandle.write(path)还有一个我不完全理解的更复杂的；filehandle.writelines("%s\n" % path for path in search_location)然而，我所做的一切都以稍微不同的方式失败了。

Answer 1

'w' 选项告诉 open() 方法覆盖 jpg_index 文件中以前的任何内容。因为每次在写入 jpeg 路径之前调用此方法，所以只剩下最后一个。使用“a”（附加）代替“w”（写入）来告诉 open() 方法附加到文件而不是每次都覆盖它。

例如：

for search_location in search_locations:

    for path in Path(search_location).rglob('*.jpg'):

        with open(jpg_index, 'a') as filehandle:

            filehandle.writelines('%s\n' % path)

或者，您可以将 with... as 语句移到 for 循环之外。这样，jpg_index 文件只会在开始时打开并覆盖一次，而不是在其中已经有信息之后。

例如：

with open(jpg_index, 'w') as filehandle:

    for search_location in search_locations:

        for path in Path(search_location).rglob('*.jpg'):

            filehandle.writelines('%s\n' % path)