结构或大内存块打包的办法（下）

The information in this article applies to:

- Microsoft Visual C++ 6.0,SP5

Version

Date

Creator

Description

1.0.0.1

2004-2-23

郑昀

草稿

// 智能流指针

CComPtr<IStream> pStream = NULL;

LARGE_INTEGER zero = {0,0};

// hGlobal是内存句柄：

LPBYTE pChunk = (BYTE *) GlobalLock(hGlobal);

// 创建一个空的stream：

HRESULT hr = CreateStreamOnHGlobal(NULL, TRUE, &pStream );

pStream->Seek( zero, STREAM_SEEK_SET, NULL );

ULONG pcbWritten = 0;

// pChunk现在已经指向我们的巨大内存块；

// 我们把这块内存写入IStream流中：

pStream->Write (pChunk, dwNumRead, &pcbWritten);

// 检查是否全部写入了：

ATLASSERT(pcbWritten==dwNumRead);

// unlock the data

GlobalUnlock(hGlobal);

// 剩下的一样，也是让CComPtr <IPersistStream>来调用Load方法加载IStream

// Create a stream holder. Load the stream holder from the global stream.

//  THIS STREAM HOLDER IS INTERITED FROM IPersistStream

//  And all virtual functions are Modified to handle the object....

CComPtr <IStreamHolder> pHolder = new CComObject <CStreamHolder>;

CComPtr <IPersistStream> pHolderStream;

hr = pHolder->QueryInterface (IID_IPersistStream, (void **)&pHolderStream);

pStream->Seek( zero, STREAM_SEEK_SET, NULL );

pHolderStream->Load(pStream);

CComVariant vComData = pHolder;

.. ..

//

// now, you have a big chunk of memory loaded into a ComVariant

//

// 现在你可以把打包后的CComVariant传递给MSMQMessege的Body属性了：

pisMsg->Body = vComData;

.. ..

//Coder: Aydin T.BAKIR

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