如果使用XML SDK处理nameingspace？

Question

操作系统： windows XP home版本
XML SDK： 4.0
开发工具： Visual C++ 6

#include "stdafx.h"
#include <stdio.h>
#include <windows.h>
#include <locale.h>

#import <msxml4.dll> raw_interfaces_only
using namespace MSXML2;

// Macro that calls a COM method returning HRESULT value:
#define HRCALL(a, errmsg) \
do { \
    hr = (a); \
    if (FAILED(hr)) { \
        dprintf( "%s:%d  HRCALL Failed: %s\n  0x%.8x = %s\n", \
                __FILE__, __LINE__, errmsg, hr, #a ); \
        goto clean; \
    } \
} while (0)

// Helper function that put output in stdout and debug window
// in Visual Studio:
void dprintf( char * format, ...)
{
    static char buf[1024];
    va_list args;
    va_start( args, format );
    vsprintf( buf, format, args );
    va_end( args);
    OutputDebugStringA( buf);
    printf("%s", buf);
}

// Helper function to create a DOM instance:
IXMLDOMDocument2 * DomFromCOM()
{
   HRESULT hr;
   IXMLDOMDocument2 *pxmldoc = NULL;

    HRCALL( CoCreateInstance(__uuidof(DOMDocument40),
                      NULL,
                      CLSCTX_INPROC_SERVER,
                      __uuidof(IXMLDOMDocument),
                      (void**)&pxmldoc),
            "Create a new DOMDocument");

    HRCALL( pxmldoc->put_async(VARIANT_FALSE),
            "should never fail");
    HRCALL( pxmldoc->put_validateOnParse(VARIANT_FALSE),
            "should never fail");
    HRCALL( pxmldoc->put_resolveExternals(VARIANT_FALSE),
            "should never fail");

   return pxmldoc;
clean:
   if (pxmldoc)
    {
      pxmldoc->Release();
    }
   return NULL;
}

int main(int argc, char* argv[])
{
   IXMLDOMDocument2 *pXMLDom=NULL;
   IXMLDOMParseError *pXMLErr=NULL;
   BSTR bstr = NULL;
   BSTR xmlStr = NULL;
   VARIANT_BOOL status;
   IXMLDOMNodeList *pNodes=NULL;
   IXMLDOMNode *pNode=NULL;

   VARIANT p1;
   VARIANT p2;
   VariantInit(&p1);
   V_BSTR(&p1) = SysAllocString(L"xmlns:soapenv='http://schemas.xmlsoap.org/soap/envelope/'");

   VariantInit(&p2);
   V_BSTR(&p2) = SysAllocString(L"xmlns:nns_0='http://www.primeton.com/com.primeton.eos.wfclient/com/primeton/eos/wfclient/wfclientservice'");

 

   CoInitialize(NULL);
    setlocale(LC_ALL,"chinese-simplified");
   pXMLDom = DomFromCOM();
   if (!pXMLDom) goto clean;

   pXMLDom->setProperty(BSTR("SelectionNamespaces"), p1);   // 使用了这个方法来注册命名空间，但是好像没起作用
   pXMLDom->setProperty(BSTR("SelectionNamespaces"), p2);

   // HRCALL(pXMLDom->load(var, &status), "");
   //xmlStr= SysAllocString(L"<?xml version='1.0'?><soapenv:Envelope xmlns:soapenv='http://schemas.xmlsoap.org/soap/envelope/'><soapenv:Body><ns_0:startWorkFlowOutMsg xmlns:ns_0='http://www.primeton.com/com.primeton.eos.wfclient/com/primeton/eos/wfclient/wfclientservice' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xsi:type='ns_0:startWorkFlowOutMsg'><ns_0:result>63</ns_0:result></ns_0:startWorkFlowOutMsg></soapenv:Body></soapenv:Envelope>"); 
xmlStr = SysAllocString(L"<?xml version='1.0'?><a>xiaojing</a>");

 pXMLDom->loadXML(xmlStr, &status);
 pXMLDom->get_xml(&bstr);

 //bstr = SysAllocString(L"/Envelope/Body/startWorkFlowOutMsg/result");
 bstr = SysAllocString(L"/a");

 pXMLDom->selectSingleNode(bstr, &pNode);
 //HRCALL(pNode->get_xml(&bstr), "get_xml: ");
 pNode->get_text(&bstr);
    dprintf("\t%S\n\n", bstr);

  
clean:
   if (bstr) SysFreeString(bstr);
   if (pXMLErr) pXMLErr->Release();
   if (pXMLDom) pXMLDom->Release();

   CoUninitialize();
   return 1;
}