Delphi 2010 RTTI : Explore Enumerations

Question

Considering such an enumeration :

type
  TTypeOfData = (
    [XmlName(\'ABC\')] todABC,
    [XmlName(\'DEF\')] todDEF,  
    [XmlName(\'GHI\')] todGHI
  );
         


        

Answer 1

For those who are interrested in a practical solution to that problem, I solved it that way :

type
  TTypeOfData = (todABC, todDEF, todGHI);

  TMySerializableClass = class
  private
    FType: TTypeOfData;
  public
    property &Type: TTypeOfData read FType write FType;
    class function TypeOfDataAsString(&Type: TTypeOfData): String;
  end;

implementation

class function TMySerializableClass.TypeOfDataAsString(&Type: TTypeOfData): String;
const
  TYPE_STRING: array[TypeOfDataAsString] of String = ('ABC', 'DEF', 'GHI);
begin
  Result := TYPE_STRING[&Type];
end;

And later, in the serialization code, I use RTTI to look for a class function conventionnaly named AsString and call it with the property TValue :

procedure Serialize(const V: TValue);
var
  N: String;
  T: TRttiType;
  F: TRttiField;
  M: TRttiMethod;
  R: TValue;
 begin
   case V.TypeInfo^.Kind of
   tkEnumeration:
   begin
     T := Ctx.GetType(TypeInfo(TMySerializableClass));
     N := V.TypeInfo.Name + 'AsString';
     if N[1] = 'T' then
       Delete(N, 1, 1);
     M := T.GetMethod(N);
     if (M <> nil) and M.IsClassMethod and (M.MethodKind = mkClassFunction) and (M.ReturnType.TypeKind = tkUString) then
     begin
       R := M.Invoke(TTicket, [V]);
       // serialize R.AsString
     end;
   end;
   ...
 end;