Author: Jonas Bilinkevicius

How can I propogate through an object's published properties and extract an actual 
class reference in order to perform operations like: if GiveProperty is 
TSomeObjectType then do something?

Answer:

1   function GetFontProp(anObj: TObject): TFont;
2   var
3     PInfo: PPropInfo;
4   begin
5     {Try to get a pointer to the property information for a 
6   	property with the name 'Font'.
7     TObject.ClassInfo returns a pointer to the RTTI table, which we need to pass
8     to GetPropInfo}
9     PInfo := GetPropInfo(anObj.ClassInfo, 'font');
10    Result := nil;
11    if PInfo <> nil then
12      {found a property with this name, check if it has the correct type}
13      if (PInfo^.Proptype^.Kind = tkClass) and
14        GetTypeData(PInfo^.Proptype^)^.ClassType.InheritsFrom(TFont) then
15        Result := TFont(GetOrdProp(anObj, PInfo));
16  end;