class Poco::XML::DocumentFragment
Overview
DocumentFragment is a “lightweight” or “minimal” Document object. More…
#include <DocumentFragment.h> class DocumentFragment: public Poco::XML::AbstractContainerNode { public: // methods virtual const XMLString& nodeName() const; virtual unsigned short nodeType() const; protected: // construction DocumentFragment(Document* pOwnerDocument); DocumentFragment( Document* pOwnerDocument, const DocumentFragment& fragment ); // methods virtual Node* copyNode( bool deep, Document* pOwnerDocument ) const; };
Inherited Members
public: // typedefs typedef Poco::XML::NamespaceSupport NSMap; // enums enum { ELEMENT_NODE = 1, ATTRIBUTE_NODE, TEXT_NODE, CDATA_SECTION_NODE, ENTITY_REFERENCE_NODE, ENTITY_NODE, PROCESSING_INSTRUCTION_NODE, COMMENT_NODE, DOCUMENT_NODE, DOCUMENT_TYPE_NODE, DOCUMENT_FRAGMENT_NODE, NOTATION_NODE, }; // methods void duplicate() const; void release() const; virtual void autoRelease() = 0; virtual void addEventListener( const XMLString& type, EventListener* listener, bool useCapture ) = 0; virtual void removeEventListener( const XMLString& type, EventListener* listener, bool useCapture ) = 0; virtual bool dispatchEvent(Event* evt) = 0; virtual const XMLString& nodeName() const = 0; const XMLString& nodeValue() const; virtual const XMLString& getNodeValue() const = 0; virtual void setNodeValue(const XMLString& value) = 0; virtual unsigned short nodeType() const = 0; virtual Node* parentNode() const = 0; virtual NodeList* childNodes() const = 0; virtual Node* firstChild() const = 0; virtual Node* lastChild() const = 0; virtual Node* previousSibling() const = 0; virtual Node* nextSibling() const = 0; virtual NamedNodeMap* attributes() const = 0; virtual Document* ownerDocument() const = 0; virtual Node* insertBefore( Node* newChild, Node* refChild ) = 0; virtual Node* replaceChild( Node* newChild, Node* oldChild ) = 0; virtual Node* removeChild(Node* oldChild) = 0; virtual Node* appendChild(Node* newChild) = 0; virtual bool hasChildNodes() const = 0; virtual Node* cloneNode(bool deep) const = 0; virtual void normalize() = 0; virtual bool isSupported( const XMLString& feature, const XMLString& version ) const = 0; virtual const XMLString& namespaceURI() const = 0; virtual XMLString prefix() const = 0; virtual const XMLString& localName() const = 0; virtual bool hasAttributes() const = 0; virtual XMLString innerText() const = 0; virtual Node* getNodeByPath(const XMLString& path) const = 0; virtual Node* getNodeByPathNS( const XMLString& path, const NSMap& nsMap ) const = 0; virtual const XMLString& nodeName() const; virtual const XMLString& getNodeValue() const; virtual void setNodeValue(const XMLString& value); virtual Node* parentNode() const; virtual NodeList* childNodes() const; virtual Node* firstChild() const; virtual Node* lastChild() const; virtual Node* previousSibling() const; virtual Node* nextSibling() const; virtual NamedNodeMap* attributes() const; virtual Document* ownerDocument() const; virtual Node* insertBefore( Node* newChild, Node* refChild ); virtual Node* replaceChild( Node* newChild, Node* oldChild ); virtual Node* removeChild(Node* oldChild); virtual Node* appendChild(Node* newChild); virtual bool hasChildNodes() const; virtual Node* cloneNode(bool deep) const; virtual void normalize(); virtual bool isSupported( const XMLString& feature, const XMLString& version ) const; virtual const XMLString& namespaceURI() const; virtual XMLString prefix() const; virtual const XMLString& localName() const; virtual bool hasAttributes() const; virtual void addEventListener( const XMLString& type, EventListener* listener, bool useCapture ); virtual void removeEventListener( const XMLString& type, EventListener* listener, bool useCapture ); virtual bool dispatchEvent(Event* evt); virtual XMLString innerText() const; virtual Node* getNodeByPath(const XMLString& path) const; virtual Node* getNodeByPathNS( const XMLString& path, const NSMap& nsMap ) const; virtual void autoRelease(); virtual Node* firstChild() const; virtual Node* lastChild() const; virtual Node* insertBefore( Node* newChild, Node* refChild ); virtual Node* replaceChild( Node* newChild, Node* oldChild ); virtual Node* removeChild(Node* oldChild); virtual Node* appendChild(Node* newChild); virtual bool hasChildNodes() const; virtual bool hasAttributes() const; virtual Node* getNodeByPath(const XMLString& path) const; virtual Node* getNodeByPathNS( const XMLString& path, const NSMap& nsMap ) const; protected: // fields static const XMLString EMPTY_STRING; // methods virtual Node* copyNode( bool deep, Document* pOwnerDocument ) const = 0; virtual bool events() const; virtual bool eventsSuspended() const; void captureEvent(Event* evt); void bubbleEvent(Event* evt); void dispatchSubtreeModified(); void dispatchNodeInserted(); void dispatchNodeRemoved(); virtual void dispatchNodeRemovedFromDocument(); virtual void dispatchNodeInsertedIntoDocument(); void dispatchAttrModified( Attr* pAttr, MutationEvent::AttrChangeType changeType, const XMLString& prevValue, const XMLString& newValue ); void dispatchCharacterDataModified( const XMLString& prevValue, const XMLString& newValue ); void setOwnerDocument(Document* pOwnerDocument); virtual void dispatchNodeRemovedFromDocument(); virtual void dispatchNodeInsertedIntoDocument(); bool hasAttributeValue( const XMLString& name, const XMLString& value, const NSMap* pNSMap ) const; static const Node* findNode( XMLString::const_iterator& it, const XMLString::const_iterator& end, const Node* pNode, const NSMap* pNSMap ); static const Node* findElement( const XMLString& name, const Node* pNode, const NSMap* pNSMap ); static const Node* findElement( int index, const Node* pNode, const NSMap* pNSMap ); static const Node* findElement( const XMLString& attr, const XMLString& value, const Node* pNode, const NSMap* pNSMap ); static const Attr* findAttribute( const XMLString& name, const Node* pNode, const NSMap* pNSMap ); static bool namesAreEqual( const Node* pNode1, const Node* pNode2, const NSMap* pNSMap ); static bool namesAreEqual( const Node* pNode, const XMLString& name, const NSMap* pNSMap );
Detailed Documentation
DocumentFragment is a “lightweight” or “minimal” Document object.
It is very common to want to be able to extract a portion of a document’s tree or to create a new fragment of a document. Imagine implementing a user command like cut or rearranging a document by moving fragments around. It is desirable to have an object which can hold such fragments and it is quite natural to use a Node for this purpose. While it is true that a Document object could fulfill this role, a Document object can potentially be a heavyweight object, depending on the underlying implementation. What is really needed for this is a very lightweight object. DocumentFragment is such an object.
Furthermore, various operations such as inserting nodes as children of another Node may take DocumentFragment objects as arguments; this results in all the child nodes of the DocumentFragment being moved to the child list of this node.
The children of a DocumentFragment node are zero or more nodes representing the tops of any sub-trees defining the structure of the document. DocumentFragment nodes do not need to be well-formed XML documents (although they do need to follow the rules imposed upon well-formed XML parsed entities, which can have multiple top nodes). For example, a DocumentFragment might have only one child and that child node could be a Text node. Such a structure model represents neither an HTML document nor a well-formed XML document.
When a DocumentFragment is inserted into a Document (or indeed any other Node that may take children) the children of the DocumentFragment and not the DocumentFragment itself are inserted into the Node. This makes the DocumentFragment very useful when the user wishes to create nodes that are siblings; the DocumentFragment acts as the parent of these nodes so that the user can use the standard methods from the Node interface, such as insertBefore and appendChild.