python - 附加到关联数组

Question

我有一个 Python 脚本，它循环访问 PDF 文件(循环遍历每个页面)，并在每个页面内进行一些文本操作。所以基本上是两个循环:

files = {}

#npages is the number of PDF pages in the specific file.

for n in range(npages):

    path = pdf_name + str(n + 1) + '_1.txt'

    files[int(n)] = path

    for i, col in enumerate(COLUMNS):

        path = pdf_name + str(n + 1) + '_' + str(i + 2) + '.txt'
        files[int(n)][int(i)] = path

基本上，我会查看每个 PDF 页面，然后在每个页面上进一步进行一些文本操作。

我正在尝试将其输出为:

- file_page_1.pdf
  - file_page_1_col_1.pdf
  - file_page_1_col_2.pdf
file_page_2.pdf
  - file_page_2_col_1.pdf
  - file_page_2_col_2.pdf

但是使用上面的 coes 会出现以下错误:

files[int(n)][int(i)] = path
TypeError: 'str' object does not support item assignment

Answer 1

我认为您正在寻找的结构是一个字典，其中包含用于列出值的字符串键。

files = {}

for page in range(npages):
    path = pdf_name + str(n+1) + '_1.txt'
    files[path] = []
    for i, col in enumerate(COLUMNS):
        subpath = pdf_name + str(n + 1) + '_' + str(i + 2) + '.txt'
        files[path].append(subpath)

# For accessing items
for path, subpaths in files.items():
    # path is a string, the key in files dict
    print(path) 
    # subpaths is a list of strings, the value in files dict
    for subpath in subpaths:
        print(subpath)

如果您希望路径/子路径对按照插入的顺序返回，您可以使用 OrderedDict 而不是 dict。

from collections import OrderedDict
files = OrderedDict()
# code as above