extents of Google map

Question

Hi, I have a Delphi application which loads a Google map in a TWebBrowser:

with WebBrowser1.Document as IHTMLDocument2 do
  with parentWindow do
    ExecScript('map.setCenter(new GLatLng(51.15917, 4.13889),10)', 'JavaScript');

Any idea of how to get the extents of the map in my application?
TIA
Steven

edit
Rob's answer points to a partial solution: javascript knows about the coordinates. I would like to get them into my Delphi application.

note on Expert's Exchange
(long answer to davidins' reply)
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Answer 1

IHTMLWindow2.execScript from the mentioned EE example should return the return value of the executed script as a Variant. But you don't have to use IHTMLDocument2.parentWindow property. There's also IHTMLDocument.Script which is an IDispatch so you can use it via Variant late binding:

var
  Document: IHTMLDocument;
  VScript, V: Variant;
begin
  Document := WebBrowser.Document as IHTMLDocument;
  VScript := Document.Script;
  V := VScript.HelloJavaScript();
  ShowMessage(V);
end;

HelloJavaScript is a javascript function returning a string:

<script language="javascript">
function HelloJavaScript()
{
    s = "Hello, world! (javascript)";
        alert(s);
        return s;
}
</script>