如何获取 Ctypes 对象的_fields_的所有内容作为 ctypes 数组？

Question

我定义了一个示例位域如下。

如何获取 _fields_ 的值作为 list/ctypes 数组？

class packet_fields(Structure):
    _fields_ = [
               ('length_present', c_int, 1),
               ('attribute_present', c_int, 1)
               ]

Answer 1

看看这段代码。使用此代码结构，您可以访问数组或数组中的元素。

class packet_fields():
    liste = [
               ('length_present', "dgr1", 1),
               ('attribute_present', "dgr2", 1)
               ]
dz= packet_fields()
print(dz.liste[1])

Answer 2

不确定你的问题，所以这里有一个关于如何获取值的例子：

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import ctypes

class packet_fields(ctypes.Structure):
    _fields_ = [
               ('length_present', ctypes.c_int, 1),
               ('attribute_present', ctypes.c_int, 1)
    ]

if __name__ == '__main__':
    pf = packet_fields()
    pf.length_present = 0
    pf.attribute_present = 1

    # list fields: name and type
    for field in pf._fields_:
        print(f"Name: {field[0]}; type: {field[1]}")

    # access value
    print(f"length_present: {pf.length_present}")
    print(f"attribute_present: {pf.attribute_present}")

    # all fields as a list
    fields_list = [getattr(pf, f[0]) for f in pf._fields_]
    print(f"As list: {fields_list}")

输出：

Name: length_present; type: <class 'ctypes.c_long'>
Name: attribute_present; type: <class 'ctypes.c_long'>
length_present: 0
attribute_present: -1
As list: [0, -1]

如果您担心 -1（而不仅仅是 1），请将 c_int 替换为 c_uint。

如何获取 Ctypes 对象的_fields_的所有内容作为 ctypes 数组？

How to get all content of _fields_ of a Ctypes object as ctypes array?

python

ctypes