fromtimestamp() 的反義詞是什麼？ (What is the opposite of fromtimestamp()?)

問題描述

fromtimestamp() 的反義詞是什麼？ (What is the opposite of fromtimestamp()?)

我正在嘗試弄清楚如何將二進製文件導入 python，但這需要大量的猜測和反複試驗。在這種情況下，我想做的是找到字節流中特定日期出現的位置，即：

import re
import datetime
import binascii
import time

with open('inputfile.nda', 'rb') as f:
    data = f.read()

# This line needs fixing
i = int.oppositeof_fromtimestamp(2019, 10, 10, 14, 53, 57.000) # '2019/10/10 14:53:57.000' 


time_stamp = i.to_bytes(4, byteorder='little')

df = [m.start() for m in re.finditer(time_stamp, data)]

print(df)

是否有一個函數（或一組函數）可以將日期轉換為字節流?

參考解法

方法 1:

You're looking for datetime.timestamp():

import datetime

ts = datetime.datetime(2019, 10, 10, 14, 53, 57)
unix_time = int(ts.timestamp())
unix_time_bytes = unix_time.to_bytes(4, byteorder='little')
print(ts, unix_time, unix_time_bytes)

outputs

2019‑10‑10 14:53:57 1570708437 b'\xd5\x1b\x9f]'

Then you'll probably want to use data.index(unix_time_bytes) to look for the string, not regexps.

(by Frederik Huld、AKX)

參考文件

1. What is the opposite of fromtimestamp()? (CC BY‑SA 2.5/3.0/4.0)