如何将Python中的数字转换为8个二进制字节（64位长）？

Question

How do I convert a number in Python to 8 binary bytes (64-bit long)?

I have a blueprint of a network message, part of which is a number represented with eight bytes.

Answer 1

Use struct.pack :

>>> import struct
>>> struct.pack('!Q', 123)
'\x00\x00\x00\x00\x00\x00\x00{'

The first argument is a format string which controls the encoding. ! means network byte order and Q is for 8-byte unsigned integers.