System.Xml.XPath.XPathNavigatorReader.Read C# (CSharp) Метод

        public override bool Read() {
            this.attrCount = -1;
            switch (this.state) {
                case State.Error:
                case State.Closed:
                case State.EOF:
                    return false;

                case State.Initial:
                    // Starting state depends on the navigator's item type
                    this.nav = this.navToRead;
                    this.state = State.Content;
                    if ( XPathNodeType.Root == this.nav.NodeType ) {
                        if( !nav.MoveToFirstChild() ) {
                            SetEOF();
                            return false;
                        }
                        this.readEntireDocument = true;
                    }
                    else if ( XPathNodeType.Attribute == this.nav.NodeType ) {
                        this.state = State.Attribute;
                    }
                    this.nodeType = ToXmlNodeType( this.nav.NodeType );
                    break;

                case State.Content:
                    if ( this.nav.MoveToFirstChild() ) {
                        this.nodeType = ToXmlNodeType( this.nav.NodeType );
                        this.depth++;
                        this.state = State.Content;
                    }
                    else if ( this.nodeType == XmlNodeType.Element 
                        && !this.nav.IsEmptyElement ) {
                        this.nodeType = XmlNodeType.EndElement;
                        this.state = State.EndElement;
                    }
                    else
                        goto case State.EndElement;
                    break;

                case State.EndElement:
                    if ( 0 == depth && !this.readEntireDocument ) {
                        SetEOF();
                        return false;
                    }
                    else if ( this.nav.MoveToNext() ) {
                        this.nodeType = ToXmlNodeType( this.nav.NodeType );
                        this.state = State.Content;
                    }
                    else if ( depth > 0 && this.nav.MoveToParent() ) {
                        Debug.Assert( this.nav.NodeType == XPathNodeType.Element, this.nav.NodeType.ToString() + " == XPathNodeType.Element" );
                        this.nodeType = XmlNodeType.EndElement;
                        this.state = State.EndElement;
                        depth--;
                    }
                    else {
                        SetEOF();
                        return false;
                    }
                    break;

                case State.Attribute:
                case State.AttrVal:
                    if ( !this.nav.MoveToParent() ) {
                        SetEOF();
                        return false;
                    }
                    this.nodeType = ToXmlNodeType( this.nav.NodeType );
                    this.depth--;
                    if (state == State.AttrVal)
                        this.depth--;
                    goto case State.Content;
                case State.InReadBinary:
                    state = savedState;
                    readBinaryHelper.Finish();
                    return Read();
            }
            return true;
        }