问题
I'm trying to create a COM Object from a dll in a new thread in Python - so I can run a message pump in that thread:
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()
this is the error trace I get:
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
Any ideas?
回答1:
You need to have called CoInitialize()
(or CoInitializeEx()
) on a thread before you can create COM objects on that thread.
from win32com.client.pythoncom import CoInitialize
CoInitialize()
回答2:
As far as I remember (long time ago I'e programmed a lot with COM Components) you have to call CoInitialize on each thread if your COM Object uses STA.
http://msdn.microsoft.com/en-us/library/ms678543(VS.85).aspx
But I've no idea how to call that function in python.
Here is the MSDN Doc
http://msdn.microsoft.com/en-us/library/ms678543(VS.85).aspx
回答3:
Just to update with current experience using PyCharm and Python 2.7: You need to import:
from pythoncom import CoInitializeEx
from pythoncom import CoUninitialize
then for running the thread:
def run(self):
res = CoInitializeEx(0)
#<your code>
CoUninitialize()
PyCharm get confused with STA apartment, you need to enable true multithreading.
It is important that each CoInitialize()
is terminated with a CoUninitialize()
, so be sure your code follows this rule in case of errors, too.
来源:https://stackoverflow.com/questions/3246525/why-cant-i-create-a-com-object-in-a-new-thread-in-python