为什么我不能在Python的新线程中创建COM对象？

我正在尝试在Python的新线程中从dll创建一个COM对象 - 所以我可以在该线程中运行消息泵:

from comtypes.client import CreateObject
import threading

class MessageThread(threading.Thread):

    def __init__(self):
        threading.Thread.__init__(self)
        self.daemon = True

    def run(self):
        print "Thread starting"
        connection = CreateObject("IDMessaging.IDMMFileConnection")
        print "connection created"

a = CreateObject("IDMessaging.IDMMFileConnection")
print "aConnection created"
t = MessageThread()
t.start()

这是我得到的错误跟踪:

aConnection created
Thread starting
>>> Exception in thread Thread-1:
Traceback (most recent call last):
  File "c:\python26\lib\threading.py", line 532, in __bootstrap_inner
    self.run()
  File "fred.py", line 99, in run
    self.connection = CreateObject("IDMessaging.IDMMFileConnection")
  File "c:\python26\lib\site-packages\comtypes\client\__init__.py", line 235, in CreateObject
    obj = comtypes.CoCreateInstance(clsid, clsctx=clsctx, interface=interface)
  File "c:\python26\lib\site-packages\comtypes\__init__.py", line 1145, in CoCreateInstance
    _ole32.CoCreateInstance(byref(clsid), punkouter, clsctx, byref(iid), byref(p))
  File "_ctypes/callproc.c", line 925, in GetResult
WindowsError: [Error -2147221008] CoInitialize has not been called

有任何想法吗？

您需要先在线程上调用CoInitialize()(或CoInitializeEx()),然后才能在该线程上创建COM对象.

from win32com.client.pythoncom import CoInitialize
CoInitialize()