初始化指针：
MSXML2::IXMLDOMDocument *pDocument=NULL;
MSXML2::IXMLDOMNodeList *pNodeList=NULL;
MSXML2::IXMLDOMNamedNodeMap *pNodeMap=NULL;
MSXML2::IXMLDOMNode *pNode=NULL
MSXML2::IXMLDOMText *pText=NULL;
MSXML2::IXMLDOMElement *pElement=NULL;
MSXML2::IXMLDOMProcessingInstruction *pProcessingInstruction=NULL;
MSXML2::IXMLDOMComment *pComment=NULL;

MSXML2::IXMLDOMParseError *pObjError = NULL;

已知数据：
BSTR bstrText, bstrName;
int  type;

**）创建新文档
// hr = CoCreateInstance(CLSID_DOMDocument, NULL, CLSCTX_INPROC_SERVER,
//  IID_IXMLDOMDocument,(void**)&m_pXMLDoc);
HRESULT hr=CoCreateInstance(__uuidof(MSXML2::DOMDocument40),NULL,CLSCTX_INPROC_SERVER,
  __uuidof(MSXML2::IXMLDOMDocument),(void**)&m_pXMLDoc);
    hr = pDocument->put_async(VARIANT_FALSE);
    hr = pDocument->put_validateOnParse(VARIANT_FALSE);
hr = pDocument->put_resolveExternals(VARIANT_FALSE);

问题1：MSXML2::IXMLDOMDocument *pDoc
          MSXML2::IXMLDOMDocument *pDocument=NULL;
着两个代码怎么解释？IXMLDOMDocument应该是一个类吧，pDoc是一个变量指针，指向一个IXMLDOMDocument类型的对象，这么理解对吗？那作用域符号前面的msxml2是什么意思？怎么解释？

问题2：hr = pDocument->put_async(VARIANT_FALSE);
    hr = pDocument->put_validateOnParse(VARIANT_FALSE);
hr = pDocument->put_resolveExternals(VARIANT_FALSE);
这三个函数是哪来的？我从msxml dsk中IXMLDOMDocument类的功能函数中找不到啊，但pDocument明明是指向IXMLDOMDocument类型对象的指针
麻烦高手给解释一下吧，刚入门，举步维艰啊，谢了