python - 读取、编辑和写入文本文件中的每 4 行

Question

长期读者第一次提问。

我正在处理一些需要编辑时间戳的 vtt(隐藏式字幕)文件。文件格式如下:

177
00:07:37.450 --> 00:07:39.690
- [Liz] How would you suggest an organization devise

178
00:07:39.690 --> 00:07:41.719
the accountabilities for culture?

179
00:07:41.719 --> 00:07:43.690
- [Tamara] It is a shared accountability  

我编写了以下代码来读取文件、计算新时间戳(慢 5%)并输出新时间戳:

from sys import argv
script, filename = argv

adjustment = input("Adjustment multiplier: ")

video = open(filename, "r+")
lines = video.readlines()

video.seek(0)

for l in lines:
    if l[:2] == "00":
        #here I've omitted a lot of calculations to turn the timestamps 
        #into milliseconds, apply the adjustment multiplier, and turn them back into
        #minutes, seconds, and milliseconds.

        new_line = str(#concatenation of new values into timestamp format)
        video.write(new_line)

video.close()

计算效果很好，但问题是它会将所有新行转储到文件的开头，而不是覆盖每个时间戳行并跳过其余行。

我很想听听你们的想法!我已经为此苦苦挣扎了一段时间，并尝试了很多方法，但还没有完全成功。

谢谢!

Answer 1

你可以试试enumerate在迭代行时，然后执行相同的过程:

# Reading code here ...

for index, line in enumerate(lines):
    if index % 4 == 0:
        # Your code here ...

希望对你有帮助:)