使用 python 写 COM

原帖地址：http://www.cppblog.com/bigsml/archive/2008/08/14/58851.html

 

Python 支持Com调用(client com) 以及撰写COM 组件(server com).
1. com 调用示例(使用Windows Media Player 播放音乐)

from win32com.client import Dispatch
mp = Dispatch("WMPlayer.OCX")
tune = mp.newMedia("C:/WINDOWS/system32/oobe/images/title.wma")
mp.currentPlaylist.appendItem(tune)
mp.controls.play()

2. com server 的编写
主要可以参考 <<Python Programming on Win32 之 Chapter 12 Advanced Python and COM http://oreilly.com/catalog/pythonwin32/chapter/ch12.html >>
示例(分割字符串)
- 代码

class PythonUtilities:
    _public_methods_ = [ 'SplitString' ]
    _reg_progid_ = "PythonDemos.Utilities"
    # NEVER copy the following ID 
    # Use "print pythoncom.CreateGuid()" to make a new one.
    _reg_clsid_ = "{41E24E95-D45A-11D2-852C-204C4F4F5020}"
    
    def SplitString(self, val, item=None):
        import string
        if item != None: item = str(item)
        return string.split(str(val), item)
 
# Add code so that when this script is run by
# Python.exe, it self-registers.
if __name__=='__main__':
    print "Registering COM server"
    import win32com.server.register
    win32com.server.register.UseCommandLine(PythonUtilities)

- 注册/注销Com

Command-Line Option

Description

 

The default is to register the COM objects.

--unregister

Unregisters the objects. This removes all references to the objects from the Windows registry.

--debug

Registers the COM servers in debug mode. We discuss debugging COM servers later in this chapter.

--quiet

Register (or unregister) the object quietly (i.e., don't report success).

- 使用COM
可以在python 命令行下运行

>>> import win32com.client
>>> s = win32com.client.Dispatch("PythonDemos.Utilities")
>>> s.SplitString("a,b,c", ",")
((u'a', u'a,b,c'),)
>>>

3. python server com 原理
其实在注册表中查找到python com 的实现内幕

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}]
@="PythonDemos.Utilities"

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/Debugging]
@="0"

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/Implemented Categories]

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/Implemented Categories/{B3EF80D0-68E2-11D0-A689-00C04FD658FF}]

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/InprocServer32]
@="pythoncom25.dll"
"ThreadingModel"="both"

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/LocalServer32]
@="D://usr//Python//pythonw.exe /"D://usr//Python//lib//site-packages//win32com//server//localserver.py/" {41E24E95-D45A-11D2-852C-204C4F4F5020}"

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/ProgID]
@="PythonDemos.Utilities"

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/PythonCOM]
@="PythonDemos.PythonUtilities"

[HKEY_CLASSES_ROOT/CLSID/{41E24E95-D45A-11D2-852C-204C4F4F5020}/PythonCOMPath]
@="D://"

inproc server 是通过pythoncom25.dll 实现
local server 通过localserver.py 实现
com 对应的python 源文件信息在 PythonCOMPath & PythonCOM

4. 使用问题
用PHP 或者 c 调用com 的时候

<?php
$com = new COM("PythonDemos.Utilities");
$rs = $com->SplitString("a b c");
foreach($rs as $r)
    echo $r."/n";
?>

会碰到下面的一些错误.
pythoncom error: PythonCOM Server - The 'win32com.server.policy' module could not be loaded.
<type'exceptions.ImportError'>: No module named server.policy pythoncomerror: CPyFactory::CreateInstance failed to create instance. (80004005)


可以通过2种方式解决:
a. 设置环境 PYTHONHOME = D:/usr/Python
另外在c ++ 使用python 的时候, 如果import module 出现错误 'import site' failed; use -v for traceback 的话, 也可以通过设置这个变量解决.

b. 为com 生产exe, dll 可执行文件, setup.py 代码如下 :

from distutils.core import setup 
import py2exe 

import sys 
import shutil 

# Remove the build tree ALWAYS do that! 
shutil.rmtree("build", ignore_errors=True) 

# List of modules to exclude from the executable 
excludes = ["pywin", "pywin.debugger", "pywin.debugger.dbgcon", "pywin.dialogs", "pywin.dialogs.list"] 

# List of modules to include in the executable 
includes = ["win32com.server"] 

# ModuleFinder can't handle runtime changes to __path__, but win32com uses them 
try: 
    # if this doesn't work, try import modulefinder 
    import py2exe.mf as modulefinder 
    import win32com 
    
    for p in win32com.__path__[1:]: 
        modulefinder.AddPackagePath("win32com", p) 
    
    for extra in ["win32com.shell", "win32com.server"]: #,"win32com.mapi" 
        __import__(extra) 
        m = sys.modules[extra] 
        for p in m.__path__[1:]: 
            modulefinder.AddPackagePath(extra, p) 

except ImportError: 
    # no build path setup, no worries. 
    pass 

# Set up py2exe with all the options 
setup( 
    options = {"py2exe": {"compressed": 2, 
                          "optimize": 2, 
                          #"bundle_files": 1, 
                          "dist_dir": "COMDist", 
                          "excludes": excludes, 
                          "includes": includes}}, 
    # The lib directory contains everything except the executables and the python dll. 
    # Can include a subdirectory name. 
    zipfile = None, 
    com_server = ['PythonDemos'], # 文件名!!
    ) 

ref:
http://oreilly.com/catalog/pythonwin32/chapter/ch12.html 
http://blog.donews.com/limodou/archive/2005/09/02/537571.aspx