Question

Using the MSXML2 functions from the “msxml3.dll” library, I’m trying to duplicate sections in an XML document, but it does not work as I expected.

Here is the XML:

<result>
     <Target>
          <Point>
            <pos dimension="2">60.384005 5.333862</pos>
          </Point>
      </Target>
</result>

What I want is to add multiple sections. So I want to take the node, duplicate it and put it under the existing <Target> node. I’m almost convinced I should use the Clone method, but it does not seem to work.
The C++ code:

    typedef MSXML2::IXMLDOMNodePtr XmlNode;  

    XmlNode pNode = pXMLRequest->selectSingleNode("//result");
if(pNode==NULL)
    { m_szErrorText =  m_szErrorText + _T(" 'result' node not found");return FALSE;}    

    XmlNode pTargetNode = pNode->selectSingleNode("Target");
    XmlNode pNewTargetNode  = pTargetNode->cloneNode(true);
    pNode->appendChild(pNewTargetNode);

But when I run this code nothing happens to the XML document. And when I inspect the XML text in pNewTargetNode I see it is '<result>' only which is just the name of the node While I would expect it to contain all the nodes in <Target>...</Target>. Is there something I am missing ?

Answer 1

I used the wrong kind of ‘true’.
If I replace

XmlNode pNewTargetNode  = pTargetNode->cloneNode(true);

with

XmlNode pNewTargetNode  = pTargetNode->cloneNode(VARIANT_TRUE);

it works fine. I had already thought about this and used TRUE instead of true, but that does not work either.
So when using the msxml library alsways use VARIANT_BOOL, VARIANT_FALSE and VARIANT_TRUE.

Raymond Chen explains why there are so many variations:
http://blogs.msdn.com/b/oldnewthing/archive/2004/12/22/329884.aspx