代码.py：#!/usr/bin/env python3
import sys
import ctypes
def get_long_data(long_obj):
py_obj_header_size = sys.getsizeof(0)
number_size = sys.getsizeof(long_obj) - py_obj_header_size
number_address = id(long_obj) + py_obj_header_size
return number_address, number_size, long_obj < 0
def hex_repr(number, size=0):
format_base = "0x{{:0{:d}X}}".format(size)
if number < 0:
return ("-" + format_base).format(-number)
else:
return format_base.format(number)
def main():
numbers = [0x00,
0x01,
-0x01,
0xFF,
0xFFFF,
0x00FFFFFF,
0x12345678,
0x3FFFFFFF,
0x40000000,
0x1111111111
]
for number in numbers:
address, size, negative = get_long_data(number)
print("Number: {:s}".format(hex_repr(number, size), size, negative))
buf = ctypes.string_at(address, size)
print(" Address: {:s}, Size: {:d}, Negative: {:},\n Data: {:}".format(hex_repr(address, size=16), size, negative, buf))
print(" ({:d}).to_bytes(): {:}".format(number, number.to_bytes(size, sys.byteorder, signed=(number < 0))))
if __name__ == "__main__":
print("Python {:s} on {:s}\n".format(sys.version, sys.platform))
main()
注意事项：get_long_data是执行此项工作的函数(其他所有功能仅用于显示/测试)
地址本身就有点无用(如果你想重建数字)，这就是为什么大小(以字节为单位)和数字的符号也会返回
末尾的数组保存了实际的数字值(这就是为什么Python中的数字会变得这么大)
对于0，sys.getsizeof只返回PyObject_VAR_HEAD的大小，用于获取结构内部的数组偏移量
[Python 3]: int.to_bytes(length, byteorder, *, signed=False)用于验证，但请注意，只有当：0 <= n < 2 ** 30时，它才会匹配我们的输出(该方法对数组内容进行一些处理，它不会直接将原始数据存储到返回的字节流中)
很明显，与数字的十六进制表示相比，输出缓冲区中的字节(4字节)反转了(0x12345678是最有说服力的例子)；这是因为小endianness(可以查看[SO]: Python struct.pack() behavior (@CristiFati's answer)了解更多详细信息)
输出：(py35x64_test) e:\Work\Dev\StackOverflow\q053657865>"e:\Work\Dev\VEnvs\py35x64_test\Scripts\python.exe" code.py
Python 3.5.4 (v3.5.4:3f56838, Aug 8 2017, 02:17:05) [MSC v.1900 64 bit (AMD64)] on win32
Number: 0x0
Address: 0x0000000074C55318, Size: 0, Negative: False,
Data: b''
(0).to_bytes(): b''
Number: 0x0001
Address: 0x0000000074C55338, Size: 4, Negative: False,
Data: b'\x01\x00\x00\x00'
(1).to_bytes(): b'\x01\x00\x00\x00'
Number: -0x0001
Address: 0x0000000074C552F8, Size: 4, Negative: True,
Data: b'\x01\x00\x00\x00'
(-1).to_bytes(): b'\xff\xff\xff\xff'
Number: 0x00FF
Address: 0x0000000074C572F8, Size: 4, Negative: False,
Data: b'\xff\x00\x00\x00'
(255).to_bytes(): b'\xff\x00\x00\x00'
Number: 0xFFFF
Address: 0x0000023286E3A6C8, Size: 4, Negative: False,
Data: b'\xff\xff\x00\x00'
(65535).to_bytes(): b'\xff\xff\x00\x00'
Number: 0xFFFFFF
Address: 0x0000023286C14FA8, Size: 4, Negative: False,
Data: b'\xff\xff\xff\x00'
(16777215).to_bytes(): b'\xff\xff\xff\x00'
Number: 0x12345678
Address: 0x0000023286DE4E88, Size: 4, Negative: False,
Data: b'xV4\x12'
(305419896).to_bytes(): b'xV4\x12'
Number: 0x3FFFFFFF
Address: 0x000002328710C128, Size: 4, Negative: False,
Data: b'\xff\xff\xff?'
(1073741823).to_bytes(): b'\xff\xff\xff?'
Number: 0x40000000
Address: 0x000002328710C108, Size: 8, Negative: False,
Data: b'\x00\x00\x00\x00\x01\x00\x00\x00'
(1073741824).to_bytes(): b'\x00\x00\x00@\x00\x00\x00\x00'
Number: 0x1111111111
Address: 0x000002328710C148, Size: 8, Negative: False,
Data: b'\x11\x11\x11\x11D\x00\x00\x00'
(73300775185).to_bytes(): b'\x11\x11\x11\x11\x11\x00\x00\x00'