You can't call a Delphi method from JavaScript.
On client side:
ajaxRequest(MainForm.UniHTMLFrame1,
'Click',
['sql='+encodeURIComponent(treeNode.SQL)]);
}
On serverside:
procedure TMainForm.UniHTMLFrame1AjaxEvent(Sender: TComponent;
EventName: string; Params: TStrings);
var S : string;
begin
if SameText(EventName, 'click') then
begin
S:=Params.Values['sql'];
DoQuery(S);
end;
end;