coinitializeex_coinitializeex 失败_coinitializeex通不过

cy model as single-thread apartment. Applications developed todayshould call CoInitializeEx rather than CoInitialize.

注：新的应用程序应该调用CoInitializeEx而不是CoInitialize，否则就会有必要在之后每个调用Com的线程中调用CoInitialize来初始化出每个线程自己的套间。

AfxOleInit实际上调用了OleInitialize，虽然它在内部也调用了CoInitializeEx，但它只能处理单线程，这是AfxOleInit和CoInitialize主要区别：

OleInitialize calls CoInitializeEx internally to initialize the COMlibrary on the current apartment. Because OLE operations are notthread-safe, OleInitialize specifies the concurrency model assingle-thread apartment.

Once the concurrency model for an apartment is set, it cannot bechanged. A call to OleInitialize on an apartment that waspreviously initialized as multithreaded will fail and returnRPC_E_CHANGED_MODE.

应用：

1. CoInitialize仅仅初始化Com，支持多线程。也就是说如果多线程调用Com接口，必须在每个线程中都调用CoInitialize。coinitializeex

2. OleInitialize初始化Com（其实也是调用CoInitializeEx），支持多线程。比CoInitialize多了一下内容：

A) Clipboard

B) Drag and drop

C) Object linking and embedding (OLE)

D) In-place activation

如果不需要这些，用CoInitialize就可以。

3.AfxOleInit是MFC对OleInitialize的封装。貌似不支持多线程，也就是说只能在主进程调用该函数，如果线程需要使用Com必须调用上面的两个来实现初始化。coinitializeex而且MSDN明确标明AfxOleInit不能在MFC的DLL中调用，否则也会造成初始化失败。

4.OleInitialize和OleUninitialize()成对使用；CoInitialize和CoUninitialize成对使用；CoInitializeEx和CoUninitialize成对使用；AfxOleInit（）由MFC自动释放。

VC++使用ADO访问ACCESS时，出现_RecordsetPtr Open卡或者_ConnectionPtrExcute卡或者_CommandPtrExcute一直卡住等莫名其妙的情况时，而语法又没有错误时，请确定初始化COM函数。

MFC程序建议使用AfxOleInit（）。

本文来自电脑杂谈，转载请注明本文网址：
https://www.pc-fly.com/a/jisuanjixue/article-44684-1.html