[ecfisa]

Hola.

Proba de este modo:

Código Delphi [-]
uses  TypInfo;
...
function MethodAssigned(aObject: TObject; const MethodName: string): Boolean;
var
  Method: TMethod;
begin
  Method:= GetMethodProp(aObject, MethodName);
  Result:= (Method.Code <> nil)and(Method.Data <> nil);
end;
...

// Un ejemplo de uso:
procedure TForm1.Button1Click(Sender: TObject);
var
  i: Integer;
begin
  for i:= 0 to ComponentCount-1 do
    if Components[i] is TEdit then
      if MethodAssigned(Components[i],'OnEnter') then
        ShowMessage(Components[i].Name+' :OnEnter asignado')
      else
        ShowMessage(Components[i].Name+' :OnEnter no asignado')
end;

Saludos.