sI have an XML file that looks like the following...
<a>
<b>
<version>1.0</version>
<c>
<Module>foo.EXE</Module>
</c>
<c>
<Module>bar.DLL</Module>
</c>
</b>
</a>
I have a COM DLL that uses MSXML2:IXMLDOMNode objects that call "selectNodes" something like...
CComPtr<MSXML2::IXMLDOMNodeList> oRes = NULL ;
HRESULT hResult = m_StartNode->selectNodes(sQuery, &oRes) ;
When sQuery is //a/b/c[Module[contains(.,'EXE')]]
, then hResult is E_FAIL and ::GetLastError() returns 0.
Admittedly, I am new to XPATH, but why wouldn't this return all the 'c' element that have a Module element containing 'EXE'.
((edit))
Other simpler XPATH expressions work. //a/b/c
for example returns all elements as expected. It appears to be when I use 'contains()' or 'ends-with()' that the XPATH fails.
Here is a complete console app that demonstrates the problem.
// XMLTest.cpp : Defines the entry point for the console application.
#include "stdafx.h"开发者_开发百科
#import <msxml3.dll> raw_interfaces_only rename("value", "xmlvalue")
int _tmain(int argc, _TCHAR* argv[])
{
CoInitialize(NULL);
CComPtr<MSXML2::IXMLDOMDocument> thedoc;
thedoc.CoCreateInstance(__uuidof(MSXML2::DOMDocument));
_variant_t filename(L"c:\\shared\\test\\BlackListSmall.xml");
VARIANT_BOOL success;
HRESULT res = thedoc->load(filename, &success);
_bstr_t sQuery = L"//a/b/c[Module[contains(.,'EXE')]]";
CComPtr<MSXML2::IXMLDOMNodeList> oRes;
thedoc->selectNodes(sQuery, &oRes);
thedoc = NULL;
oRes = NULL;
CoUninitialize();
return 0;
}
and this is the contents of stdafx.h
#pragma once
#include "targetver.h"
#include <stdio.h>
#include <tchar.h>
#ifndef STRICT
#define STRICT
#endif
#define _ATL_APARTMENT_THREADED
#define _ATL_NO_AUTOMATIC_NAMESPACE
#define _ATL_CSTRING_EXPLICIT_CONSTRUCTORS // some CString constructors will be explicit
#include <atlbase.h>
#include <atlcom.h>
#include <atlctl.h>
using namespace ATL;
BTW, when I run this and get to the selectNodes() call, I get three messages in the debugger output window...
First-chance exception at 0x7564fbae in XMLTest.exe: 0xE0000001: 0xe0000001.
First-chance exception at 0x7564fbae in XMLTest.exe: 0xE0000001: 0xe0000001.
First-chance exception at 0x7564fbae in XMLTest.exe: 0xE0000001: 0xe0000001.
... and the callstack provides no real info when I break on all exceptions.
((Final Edit)) I awarded the answer to Dimitre, see below. Here are the changes I made to my example program according to his answer...
#import <msxml4.dll> raw_interfaces_only rename("value", "xmlvalue")
...
CComPtr<MSXML2::IXMLDOMDocument2> thedoc; //changed from IXMLDOMDocument
...
HRESULT res = thedoc->load(filename, &success); // unchanged
_bstr_t lang = L"SelectionLanguage"; // inserted
_variant_t xpathlang = L"XPath"; // inserted
thedoc->setProperty(lang,xpathlang); // inserted
_bstr_t sQuery = L"//a/b/c[Module[contains(.,'EXE')]]"; //unchanged
...
Thanks again Dimitre
You have to issue this on the document object:
setProperty("SelectionLanguage", "XPath");
before calling the SelectNodes()
methd with XPath expressions.
The default value is not XPath but some earlier selection language.
you want:
"//a/b/c[contains(./Module/text(),'EXE')]"
Assuming you want the c elements that have a Module child element having text that contains the string 'EXE'
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