mocking event questions

public class Mercedes : ICar
{
   ... 
   public void OnOutOfGas(EventArgs e)
   {
       // Assign to a local variable to avoid race condition
      EventHandler myEvent = OutOfGas;
      if (myEvent != null)
      {
          myEvent(this,e);
      }
}

[Test]
public void EventuallyRunOutOfGas()
{
   MockObject mockCarControl = MockManager.MockObject(typeof(Mercedes));
   // mock all methods that are not needed.
   ...
    Mercedes car = mockCarControl.Object as Mercedes;
    Driver driver = new driver(car);
    driver.ZipAround();
    // tell the car to run out of gas….
    car.OnOutOfGas(null);

    Assert.IsFalse(driver.Driving);
}

event EventHandler registeredEvent; 
public bool SaveParameter(ParameterCheckerEventArgs 
{
   registeredEvent = (EventHandler)args.ArgumentValue;
   return true;
}

[Test]
public void EventuallyRunOutOfGas()
{
   MockObject mockCarControl = MockManager.MockObject(typeof(ICar));
   // following line will call SaveParameter when event is added 
   mockCarControl.ExpectCall("add_OutOfGas").Args(new ParameterCheckerEx(SaveParameter));
   ICar mockCar = mockCarControl.Object as ICar;
   Driver driver = new Driver(mockCar);
   driver.ZipAround();
   // tell the mock car to run out of gas….
   registeredEvent(this,null);

   Assert.IsFalse(driver.Driving);
}