如何從文本文件中刪除所有行直到特定字符串？

Question

我有一個文本文件，里面有很多調試信息，在我需要的數據之前。 我正在使用 python3 嘗試重寫輸出，以便文件以特定的 JSON 標記開頭。 我試圖使用這個解決方案Remove string and all lines before string from file但我得到一個空的輸出文件，所以我認為它沒有找到 JSON 標簽。

這是我的代碼：

tag = '"meta": ['
tag_found = False 

with open('file.in',encoding="utf8") as in_file:
with open('file.out','w',encoding="utf8") as out_file:
    for line in in_file:
        if tag_found:
            if line.strip() == tag:
                tag_found = True 
            else:
                out_file.write(line)

Answer 1

tag = '"meta": ['
lines_to_write = []
tag_found = False

with open('file.in',encoding="utf8") as in_file:
    for line in in_file:
        if line.strip() == tag:
            tag_found = True
        if tag_found:
            lines_to_write.append(line)
with open('file.out','w',encoding="utf8") as out_file:
    out_file.writelines(lines_to_write)

Answer 2

您的 tag_found 始終為 False：

tag = '"meta": ['
tag_found = False 

with open('file.in',encoding="utf8") as in_file:
with open('file.out','w',encoding="utf8") as out_file:
    for line in in_file:
        if not tag_found and line.strip() == tag:
            tag_found = True
            continue

        if tag_found:
             out_file.write(line)