public void Listar()
 {
     List<Empleado> ar = new EmpleadoBL().List();
     if (ar.ToList().Count() > 0)
     {
         GridView1.DataSource = ar.ToList();
         GridView1.DataBind();
         //Formato();
     }
     else
     {
         GridView1.DataSource = null;
         GridView1.DataBind();
     }
 }