python - 如何检测字符串是否已更改

Question

我想检查特定字符串的值是否发生了变化。这些值总是随时间变化。如果字符串已更改，我只想执行操作。该字符串从文本文件中获取其值。所以我想知道文本文件是否已更改。我不知道最好的方法是什么。

with open(settings.txt, 'r') as text_file:
        custom_string = text_file.read().split("\n")[1]

if #custom_string has changed
    print("string has changed to", custom_string)

Answer 1

import time
file = open("PATH TO THE FILE", "r")
check_list = file.readlines()
actual_list = []
def check():
    global check_list, actual_list
    actual_list = file.readlines()
    for i in range(len(check_list)):
        if len(actual_list >= len(check_list):
            if check_list[i] == actual_list[i]:
                pass
            else:
                print("The file changed !")
                check_list = actual_list
                break
        else:
            if actual_list[i] == check_list[i]:
                pass
            else:
                print("The file changed !")
                check_list = actual_list
                break
while True:
    check()
    time.sleep(5)

这将每 5 秒检查一次文件是否更改