Some basic implementation methods for using msxml dom in VC

Known variables
Msxml2: ixmldomdocument * pdoc;
Msxml2: ixmldomnode * pchild, * pparent;
Msxml2: ixmldomnode * pnod;
Msxml2: ixmldomelement * Pele;

Initialization pointer:
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;

Known Data:
BSTR bstrtext, bstrname;
Int type;

**) Create a new document
// 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 );
 

A) add a child node to the parent node
Pparent-> appendchild (pchild, & pnode)
 

B) Create a node
Variant vtype;
Vtype. Vt = vt_i4;
V_i4 (& vtype) = (INT) type;
Pdoc-> createnode (vtype, bstrname, null, & pnode );

C) Create an element node
Pdoc-> createelement (bstrname, pelement );
(Pelement)-> put_text (bstrtext );

D) Create a text subnode and add it to the parent node.
Pdoc-> createtextnode (bstrtext, & ptext );
Pparent-> appendchild (ptext, & pnode)

E) Create // create a Processing Instruction element.
BSTR bstrtarget = sysallocstring (L "XML ");
BSTR bstrdata = sysallocstring (L "version = '1. 0 '");
Pdoc-> createprocessinginstruction (bstrtarget, bstrdata, & pprocessinginstruction );
Sysfreestring (bstrtarget );
Sysfreestring (bstrdata );

F) Create a comment Node
Pdoc-> createcomment (bstrtext, & pcomment );

G) Element Node Attribute Value
Get Attribute Value
Variant V;
Pele-> getattribute (bstrname, & V );
Cstring STR = V. bstrval;
Set attribute values
Ccomvariant V (STR );
Pele-> setattribute (bstrname, V );

H) node attribute value
variant V;
cstring STR;
long mcount;
get the node attribute set
hR = pnod-> get_attributes (& pnodemap);
hR = pnodemap-> get_length (& mcount );
Get node attributes
hR = pnodemap-> getnameditem (bstrname, & pnode);
pnodemap-> get_item (I, & pnode );
get the node property value
hR = pnode-> get_node value (& V);
STR = v. bstrval;
delete node attributes
msxml2: ixmldomnode * moldnode;
mnodemape-> removenameditem (bstrname, & moldnode);
If (moldnode! = NULL) moldnode-> release ();

I) node
(1) obtain the node and Node Set
Based on the node name
Pdoc-> getelementsbytagname (bstrname, & pnodelist );
Pnodelist-> get_item (0, & pnode );
Obtain the subnode set.
HR = pnod-> get_childnodes (& mnodelist );
Long mcount;
Msxml2: ixmldomnode * pnodesub;
Mnodelist-> get_length (& mcount );
HR = pnode-> get_firstchild (& pnodesub );
Delete a subnode (including deleting node attributes, subnodes, and current nodes)
Delete the current subnode
Pnodelist-> get_item (I, & pnode );
Pnod-> removechild (pnode, & moldnode );
Moldnode-> release ();

(2) Get the node name based on the node
Pnod-> get_nodename (& bstrname );
(3) obtain the node value based on the node
Variant V;
HR = pnod-> get_nodeValue(& V );

J) XML file operations
Load
Variant_bool status;
Variant vfilename;
(1)
Pdoc-> loadxml (bstrname, & status );
(2)
V_bstr (& vfilename) = strfilename. allocsysstring ();
V_vt (& vfilename) = vt_bstr;
Vresult = pdoc-> load (vfilename, & status );
Save
BSTR pbfname = mfilename. allocsysstring ();
Ccomvariant V (pbfname );
HR = pdoc-> Save (v );

BSTR = NULL;
Pdoc-> get_xml (& BSTR );

K) handle errors
BSTR = NULL;
Pdoc-> get_parseerror (& pobjerror );
Pobjerror-> get_reason (& BSTR );
Afxmessagebox (_ T ("failed to load DOM from books. xml. % s \ n"), * BSTR );