从文件追加特定行，在 For 循环内打开每个文件

Question

我有 4 个装满 txt 文档的文件夹。我使用下面的代码提取所有 txt 并将它们附加到列表中。

Doc1 = glob.glob('path*.txt')
Doc2 = glob.glob('path*.txt')
Doc3 = glob.glob('path*.txt')
Doc4 = glob.glob('path*.txt')

lines = []

for file in Doc1:     ### repeated this block for Doc2, Doc3 and Doc4 ####
     f = open(file,'r')
     lines.append(f.readlines())
     f.close()

上面的这段代码工作得很好。然而，现在我想做的是：

对于文件夹中的每个 txt 文档，我只想在开始和结束之间附加行，以删除不必要的文本。所有文件夹中的每个文档的开始和结束文本都是相同的。我尝试这样做：

for file in Doc1:
     f = open(file,'r')                    #this opens the file
     for line in file:                     #for each line in the file
         tag = False                       #tag set to False, initially
        if line.startswith('text'):        #if it starts with this text then:
             tag = True                    #tag changes to True
        elif 'end text' in line:           #if it this text is in the line then:
             tag = False                   #tag stays false
             lines.append(f.readlines())   #append this line (but now tag stays False)
        elif tag:                          # if tag is true, then append that line
             lines.append(f.readlines())
    f.close()

此代码运行时，我没有收到任何警告或错误。但是没有行附加到行。 TIA 寻求任何建议和帮助。

Answer 1

这是因为您使用的是 line，是字符串形式的文件，未读，要做到这一点，你可以这样做：

for line in f:
   # write code here

所以你的代码变成这样：

import glob
Doc1 = glob.glob('path*.txt')
Doc2 = glob.glob('path*.txt')
Doc3 = glob.glob('path*.txt')
Doc4 = glob.glob('path*.txt')

lines = []

for file in Doc1:
     f = open(file,'r')                    #this opens the file
     for line in f:                     #for each line in the file
        tag = False                       #tag set to False, initially
        if line.startswith('text'):        #if it starts with this text then:
            tag = True                    #tag changes to True
        elif 'end text' in line:           #if it this text is in the line then:
            tag = False                   #tag stays false
            lines.append(f.readlines())   #append this line (but now tag stays False)
        elif tag:                          # if tag is true, then append that line
            lines.append(f.readlines())
     f.close()

Answer 2

标签在每次迭代时都会被重置，这意味着除了其中包含 end text 的行之外，它不会输出任何内容。此外，需要对操作进行一些重新排序。

lines = []
for p in Doc1:
    tag = False  # Set the initial tag to False for the new file.
    with open(p, 'r') as f:
        for line in f:
            if tag:  # First line will never be printed since it must be a start tag
                lines.append(line)
            if  line.startswith('start'):  # Start adding from next line
                tag = True
            elif 'end' in line:  # Already added the line so we can reset the tag
                tag = False

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