python写dll接口_如何从python中的dll加载具有自定义接口的COM对象？

大家好。

任务是使用从dll加载的COM对象(禁止使用regsvr32)。该对象还公开了我将来需要的DirectShow接口。在

然后我试图使用this link中的示例获取一个模块&＃xff0c;但遇到了一个问题&＃xff1a;pythoncom对DirectShow接口(例如IBaseFilter)一无所知。而且from this post我觉得pythoncom不支持定制的COM接口&＃xff0c;但那是在2008年&＃xff0c;也许事情已经改变了&＃xff1f;在

代码是# -*- coding: utf-8 -*-

import ctypes, inspect, os, pythoncom, sys

from comtypes import client

from ctypes import OleDLL, c_long, byref

from uuid import UUID

#dshow is a module with DirectShow constants, etc

cmd_subfolder &＃61; os.path.realpath(os.path.abspath(os.path.join(os.path.split(inspect.getfile( inspect.currentframe() ))[0],"path_to_dshow_module")))

if cmd_subfolder not in sys.path:

sys.path.insert(0, cmd_subfolder)

import dshow

#that way comtypes gets to know about DirectShow interfaces

qedit &＃61; client.GetModule("qedit.dll")

dll_path &＃61; os.path.join(cmd_subfolder, "../my_path/my_dshow_filter.ax") #specifying path to dll

iid_interface &＃61; dshow.CLSID_IUnknown

iid_ibasefilter &＃61; dshow.CLSID_IBaseFilter

clsid_class &＃61; UUID(dshow.CLSID_my_filter).bytes_le

iclassfactory &＃61; UUID(str(pythoncom.IID_IClassFactory)).bytes_le

com_classfactory &＃61; c_long(0)

my_dll &＃61; ctypes.oledll.LoadLibrary(dll_path)

#getting com_classfactory pointer to an adress of IClassFactory within loaded dll

hr &＃61; my_dll.DllGetClassObject(clsid_class, iclassfactory, byref(com_classfactory))

#creating class factory from adress using pythoncom

MyFactory &＃61; pythoncom.ObjectFromAddress(com_classfactory.value, pythoncom.IID_IClassFactory)

#creating COM object using IClassFactory::CreateInstance, using IUnknown as a default interface

dmx_interface &＃61; MyFactory.CreateInstance(None, iid_interface)

# I could&＃39;ve tried to use IBaseFilter directly,

# but pythoncom knows nothing about DirectShow interfaces!

# dmx &＃61; dmx_interface.QueryInterface(str(qedit.IBaseFilter._iid_)) #that yields an error

dmx &＃61; dmx_interface.QueryInterface(iid_ibasefilter) #that yields the same error

我得到的错误是TypeError: There is no interface object registered that supports this IID&＃xff0c;这是可以理解的。在

所以&＃xff0c;通信类型知道这些接口&＃xff01;但不幸的是&＃xff0c;我找不到使用comtypes或甚至ctypes从dll加载COM对象的方法。在

我已经处理这个问题好几天了&＃xff0c;如果你能给我一些建议&＃xff0c;我将不胜感激。在