VC read/write XML

Today, we have performed some simple read/write operations on the XML file. The specific implementation steps are as follows:

First, create a dialog-based MFC project named operatexml, and then add two buttons ("CREATE" and "getdata" and a listcontrol
Control (used to display data), first import to the database file
# Import "msxml3.dll"
Using namespace msxml2;
It is mainly used to perform operations on XML files,
Double-click the "Create" button to write the code as follows:
Void coperatexml: onbtncreate ()
{
// Todo: add your control notification handler code here
: Coinitialize (null); // initialize com
Msxml2: ixmldomdocumentptr pdoc;
Msxml2: ixmldomelementptr xmlroot;
Hresult hR = pdoc. createinstance (_ uuidof (msxml2: domdocument30 ));
If (! Succeeded (HR ))
{
MessageBox ("error ");
Return;
}
Pdoc-> raw_createelement (_ bstr_t) (char *) "China", & xmlroot );
Pdoc-> raw_appendchild (xmlroot, null );

Msxml2: ixmldomelementptr childnode;
Pdoc-> raw_createelement (_ bstr_t) (char *) "city", & childnode );
Childnode-> puttext ("Shanghai ");
Childnode-> setattribute ("population", "7000 ");
Childnode-> setattribute ("area", "2000 ");
Xmlroot-> appendchild (childnode );

Pdoc-> raw_createelement (_ bstr_t) (char *) "city", & childnode );
Childnode-> puttext ("Beijing ");
Childnode-> setattribute ("population", "39999 ");
Childnode-> setattribute ("area", "3322 ");
Xmlroot-> appendchild (childnode );

Pdoc-> Save ("D: // test. xml ");
}

Double-click the "getdata" button to write the code as follows:
Void coperatexml: onbtnget ()
{
// Todo: add your control notification handler code here
M_list.deleteallitems ();
Msxml2: ixmldomdocumentptr pdoc;
Hresult hR = pdoc. createinstance (_ uuidof (msxml2: domdocument30 ));
If (! Succeeded (HR ))
{
MessageBox ("error! ");
Return;
}
Pdoc-> load ("D: // test. xml ");
Msxml2: ixmldomelementptr childnode;
Childnode = (msxml2: ixmldomelementptr) (pdoc-> selectsinglenode ("// City "));

Msxml2: domnodetype nodetype;
Childnode-> get_nodetype (& nodetype );

Msxml2: ixmldomnamednodemapptr pattrs = NULL;
Msxml2: ixmldomnodelistptr nodelist;
Msxml2: ixmldomnodeptr pattritem;
Childnode-> get_attributes (& pattrs );
Childnode-> get_childnodes (& nodelist );
Long ncount, icount;
Pattrs-> get_length (& ncount); // gets the number of node attributes
Nodelist-> get_length (& icount); // obtain the number of nodes
For (INT I = 0; I <icount; I ++) // you can add data to listcontrol as needed.
{
For (Int J = 0; j <ncount; j ++)
{
Pattrs-> get_item (J, & pattritem );
Cstring strattrname = (char *) (_ bstr_t) pattritem-> nodename;
Cstring strattrvalue = (char *) (_ bstr_t) pattritem-> nodetypedvalue;
M_list.insertitem (I, strattrname );
M_list.setitemtext (I, 1, strattrvalue );
}
}

}

Binds an operation variable to the listcontrol control.

Clistctrl m_list;

Initialize oninitdialog with the following code:

Bool coperatexml: oninitdialog ()
{
// Todo: add extra initialization here
M_list.insertcolumn (0, "Population ");
M_list.insertcolumn (1, "num ");
M_list.insertcolumn (1, "area ");
M_list.insertcolumn (1, "num ");
Crect rect;
M_list.getclientrect (& rect );
Int width = (rect. Right-rect. Left)/4;
M_list.setcolumnwidth (0, width );
M_list.setcolumnwidth (1, width );
M_list.setcolumnwidth (2, width );
M_list.setcolumnwidth (3, width );
}

F7 Compilation Program, CTRL + F5 to view the display results, so far a simple XML file operation has been completed successfully.