RttiInvoke.dpr

program Project1;

{$APPTYPE CONSOLE}

{$R *.res}

uses
  System.Rtti,
  System.SysUtils;

type
{$M+}
  IFoo = interface
    ['{65C02E99-4136-4572-B2C7-365AEA174E6E}']
    function GetBar: String;
  end;
{$M-}

{$RTTI EXPLICIT METHODS([vcPrivate, vcProtected, vcPublic, vcPublished])}
  TFoo = class(TInterfacedObject, IFoo)
  strict private
    function GetBar: String;
  end;

function TFoo.GetBar: String;
begin
  Result := 'Bar';
end;

var
  LMethod: TRttiMethod;
  LFoo: IFoo;
begin
  LFoo := TFoo.Create;

  LMethod := TRttiContext.Create.GetType(TFoo).GetMethod('GetBar');
  Writeln(LMethod.Invoke(LFoo as TObject, []).AsString); //Prints: Bar

  LMethod := TRttiContext.Create.GetType(TypeInfo(IFoo)).GetMethod('GetBar');
  Writeln(LMethod.Invoke(LFoo as TObject, []).AsString); //Access Violation

  ReadLn;
end.