Example 850. The method to define and implement the handler class

// handler class
class MyXMLHandler : public SFXXMLDefaultHandler {
public:
    explicit MyXMLHandler(Void);
    virtual ~MyXMLHandler(Void);

    // declaration for each handler

    // handlers for obtaining content of XML document
    virtual Void Characters(SFXAnsiStringConstRef string, BoolConst cdataSection = true);
    virtual Void EndDocument(Void);
    virtual Void EndElement(SFXAnsiStringConstRef uri = SFXAnsiString::EmptyInstance(), SFXAnsiStringConstRef localname = SFXAnsiString::EmptyInstance(), SFXAnsiStringConstRef qname = SFXAnsiString::EmptyInstance());
    virtual Void StartDocument(Void);
    virtual Void StartElement(SFXAnsiStringConstRef uri, SFXAnsiStringConstRef localname, SFXAnsiStringConstRef qname, SFXXMLGrammar::XMLAttrListConstRef attrList);
    virtual Void IgnorableWhitespace(SFXAnsiStringConstRef string);
    virtual Void ProcessingInstruction(SFXAnsiStringConstRef target, SFXAnsiStringConstRef data);
    virtual Void EndPrefixMapping(SFXAnsiStringConstRef  prefix);
    virtual Void StartPrefixMapping(SFXAnsiStringConstRef prefix, SFXAnsiStringConstRef uri);
 
   // handlers for parsing XML document
    virtual Void Comment(SFXAnsiStringConstRef string);
    virtual Void EndCDATA(Void);
    virtual Void EndDTD(Void);
    virtual Void EndEntity(SFXAnsiStringConstRef name);
    virtual Void StartCDATA(Void);
    virtual Void StartDTD(SFXAnsiStringConstRef name, SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId);
    virtual Void StartEntity(SFXAnsiStringConstRef name);

   // handlers for processing DTD
    virtual Void NotationDecl(SFXAnsiStringConstRef name, SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId);
    virtual Void UnparsedEntityDecl(SFXAnsiStringConstRef name, SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId, SFXAnsiStringConstRef notationName);

   // handlers to be notified of having received each declaration
    virtual Void ElementDecl(SFXAnsiStringConstRef name, SFXAnsiStringConstRef model);
    virtual Void AttributeDecl(SFXAnsiStringConstRef ename, SFXAnsiStringConstRef aname, SFXAnsiStringConstRef type, SFXAnsiStringConstRef valuedefault, SFXAnsiStringConstRef value);
    virtual Void InternalEntityDecl(SFXAnsiStringConstRef name, SFXAnsiStringConstRef value);
    virtual Void ExternalEntityDecl(SFXAnsiStringConstRef name, SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId);

   // handlers to be notified of having received error message
    virtual Void ErrorReport(SFCErrorConst error, SFXAnsiStringConstRef errInfo);
};

// constructor
MyXMLHandler::MyXMLHandler(Void)
{
    return;
}

// destructor
MyXMLHandler::~MyXMLHandler(Void)
{
    return;
}

// handler to receive the notification of the start of a document
Void MyXMLHandler::StartDocument(Void)
{
    TRACE("document start");
}

// handler to receive the notification of the end of a document
Void MyXMLHandler::EndDocument(Void)
{
    TRACE("document end");
}

// handler to receive the notification of the start of an element
Void MyXMLHandler::StartElement(SFXAnsiStringConstRef uri,
    SFXAnsiStringConstRef localname, SFXAnsiStringConstRef qname,
    SFXXMLGrammar::XMLAttrListConstRef attrList)
{
    // display name of the element
    TRACE("element: %s start", qname.GetCString());

    // get enumerator for first attribute of the element
    SFXXMLGrammar::XMLAttrList::Enumerator etor = attrList.GetFirstEnumerator();
    
    // display each name and its value of attributes
    while (etor.HasNext()) {
 SFXXMLGrammar::LPXMLATTR attr = etor.GetNext();     // gete next attribute
        
        TRACE("attrname: %s", attr->_attName.GetCString());  // display name of attribute
        TRACE("attrvalue: %s", attr->_value.GetCString());   // display value of attribute
    }

}

// handler to receive the notification of the end of an element
Void MyXMLHandler::EndElement(SFXAnsiStringConstRef uri,
    SFXAnsiStringConstRef localname, SFXAnsiStringConstRef qname)
{
    TRACE("element: %s end", qname.GetCString());
}

// handler to receive the notification of a character data
Void MyXMLHandler::Characters(SFXAnsiStringConstRef string,
    BoolConst /*cdataSection*/)
{
    TRACE("text: %s", string.GetCString());
    return;
}

// following are empty handlers (must be defined even if event is ignored)

// handler to receive the notification of a unnecessary white space
Void MyXMLHandler::IgnorableWhitespace(SFXAnsiStringConstRef string)
{
    return;
}

// handler to receive the notification of a processing instruction
Void MyXMLHandler::ProcessingInstruction(SFXAnsiStringConstRef target,
    SFXAnsiStringConstRef data)
{
    return;
}

// handler to receive the notification of the end of a mapping between prefix and namespace URI
Void MyXMLHandler::EndPrefixMapping(SFXAnsiStringConstRef  prefix)
{
    return;
}

// handler to receive the notification of the start of a mapping between prefix and namespace URI
Void MyXMLHandler::StartPrefixMapping(SFXAnsiStringConstRef  prefix,
    SFXAnsiStringConstRef uri)
{
    return;
}

// handler to receive the notification of a comment
Void MyXMLHandler::Comment(SFXAnsiStringConstRef string)
{
    return;
}

// handler to receive the notification of the end of a CDATA section
Void MyXMLHandler::EndCDATA(Void)
{
    return;
}

// handler to receive the notification of the end of a DTD declaration
Void MyXMLHandler::EndDTD(Void)
{
    return;
}

// handler to receive the notification of the end of an entity
Void MyXMLHandler::EndEntity(SFXAnsiStringConstRef name)
{
    return;
}

// handler to receive the notification of the start of a CDATA section
Void MyXMLHandler::StartCDATA(Void)
{
    return;
}

// handler to receive the notification of the start of a DTD declaration
Void MyXMLHandler::StartDTD(SFXAnsiStringConstRef name,
    SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId)
{
    return;
}

// handler to receive the notification of the start of an entity
Void MyXMLHandler::StartEntity(SFXAnsiStringConstRef name)
{
    return;
}

// handler to receive the notification of a notation declaration
Void MyXMLHandler::NotationDecl(SFXAnsiStringConstRef name,
    SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId)
{
    return;
}

// handler to receive the notification of the declaration of an unparsed entity
Void MyXMLHandler::UnparsedEntityDecl(SFXAnsiStringConstRef name,
    SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId,
    SFXAnsiStringConstRef notationName)
{
    return;
}

// handler to receive the notification of an element type declaration
Void MyXMLHandler::ElementDecl(SFXAnsiStringConstRef name,
    SFXAnsiStringConstRef model)
{
    return;
}

// handler to receive the notification of an ATTLIST declaration
Void MyXMLHandler::AttributeDecl(SFXAnsiStringConstRef ename,
    SFXAnsiStringConstRef aname, SFXAnsiStringConstRef type,
    SFXAnsiStringConstRef mode, SFXAnsiStringConstRef value)
{
    return;
}

// handler to receive the notification of an internal entity declaration
Void MyXMLHandler::InternalEntityDecl(SFXAnsiStringConstRef name,
    SFXAnsiStringConstRef value)
{
    return;
}

// handler to receive the notification of an external entity declaration
Void MyXMLHandler::ExternalEntityDecl(SFXAnsiStringConstRef name,
    SFXAnsiStringConstRef publicId, SFXAnsiStringConstRef systemId)
{
    return;
}

// handler to receive the notification of an error
Void MyXMLHandler::ErrorReport(SFCErrorConst error,
    SFXAnsiStringConstRef errInfo)
{
    return;
}