XML parsing, TXMLDocument

Question

I have a problem with parsing XML.

How to get field values se_url and phrase?
I need to get link1_1, link1_2

Answer 1

If you first include these 3 general purpose library routines ....

uses XMLDoc, XMLIntf, xmldom;

function CreateXMLDocument( var Owner1: TComponent): TXMLDocument;
begin
Owner1 := TComponent.Create( nil);
result  := TXMLDocument.Create( Owner1);
result.Options := [doNodeAutoCreate, doNodeAutoIndent, doAttrNull,
                   doAutoPrefix, doNamespaceDecl];
result.DOMVendor := GetDOMVendor( 'MSXML');
end;

function XPATHSelect( const FocusNode: IXMLNode; const sXPath: string): TArray;
var
  DomNodeSelect: IDomNodeSelect;
  DOMNode      : IDomNode;
  DocAccess    : IXmlDocumentAccess;
  Doc          : TXmlDocument;
  DOMNodes     : IDOMNodeList;
  iDOMNode     : integer;
begin
SetLength( result, 0);
if assigned( FocusNode) and
   Supports( FocusNode.DOMNode, IDomNodeSelect, DomNodeSelect) then
    DOMNodes := DomNodeSelect.SelectNodes( sXPath);
if not assigned( DOMNodes) then exit;
SetLength( result, DOMNodes.Length);
for iDOMNode := 0 to DOMNodes.Length - 1 do
  begin
  Doc := nil;
  DOMNode := DOMNodes.item[iDOMNode];
  if Supports( DOMNode, IXmlDocumentAccess, DocAccess) then
    Doc := DocAccess.DocumentObject;
  result[ iDOMNode] := TXmlNode.Create( DOMNode, nil, Doc) as IXMLNode;
  end
end;


function XPATHSelectFirst( const FocusNode: IXMLNode; const sXPath: string; var SelectedNode: IXMLNode): boolean;
var
  DomNodeSelect: IDomNodeSelect;
  DOMNode      : IDomNode;
  DocAccess    : IXmlDocumentAccess;
  Doc          : TXmlDocument;
begin
SelectedNode := nil;
if assigned( FocusNode) and
   Supports( FocusNode.DOMNode, IDomNodeSelect, DomNodeSelect) then
  DOMNode := DomNodeSelect.selectNode( sXPath);
if assigned( DOMNode) and
   Supports( DOMNode.OwnerDocument, IXmlDocumentAccess, DocAccess) then
  Doc := DocAccess.DocumentObject;
if Assigned( DOMNode) then
  SelectedNode := TXmlNode.Create( DOMNode, nil, Doc);
result := assigned( SelectedNode)
end;

Then A much neater solution is ...

procedure TForm2.btn1Click(Sender: TObject);
const
  DocumentSource =  'http://softez.pp.ua/gg.xml';
var
  Doc: IXMLDocument;
  DocOwner: TComponent;
  RowNode, PhraseNode, UrlNode: IXMLNode;

  procedure PutLn( const LineFmt: string; const Args: array of const);
  begin
  memo2.Lines.Add( Format( LineFmt, Args))
  end;

begin
memo2.Clear;
Doc := CreateXMLDocument( DocOwner);
Doc.LoadFromFile( DocumentSource);
for RowNode in XPATHSelect( Doc.DocumentElement, '//row[phrase]') do
  begin
  if not XPATHSelectFirst( RowNode, 'phrase', PhraseNode) then continue;
  PutLn( 'phrase=%s', [PhraseNode.NodeValue]);
  for UrlNode in XPATHSelect( RowNode, 'search_engines/search_engine/se_url') do
    PutLn( 'url=%s', [UrlNode.NodeValue]);
  PutLn('--------------',[])
  end;
DocOwner.Free;
end;

This was tested on Delphi 2010 and works a treat.