XPath in Delphi7?

Question

What is the best way of searching XML documents using XPath in Delphi7?

Answer 1

It depends on the size of the xml document. But I have good experience with both MSXML and its Saxon counterpart.

If the xml is large (>50 MB) or the queries are heavy (use some // to make your system crawl) expect some delay time. But else it is perfectly doable.

In later versions, msxml is available as a unit. In version 7 you need to install a type library:

• Go to Project\Import type library
• Select Microsoft XML, (the highest version you can find)
• Select Create unit to create MSXML_TLB

You can use MSXML_TLB to read xml documents, use xslt and perform xpath queries:

var
  doc  : IXMLDomDocument2;
  list : IXMLDomNodeList;
  node : IXMLDomNode;
  i    : Integer;

begin
  doc := CoDOMDocument.Create;
  doc.load(xmlfilename); 

  list := doc.selectNodes(xpath);
  for i := 0 to list.length-1 do begin
    node := list.item[i];
    if node<>nil then
      Memo1.Lines.Add(node.nodeName);
  end;
end;

Answer 2

When I have to deal with XML files in Delphi I always use OmniXML, a component I've been using for years. I'm totally happy with it, mainly because it's light, easy to use and free.

And it works with XPath in a easy way also. It's worth a try, I hope it helps you also.