car.cs

asp.net经典案例资料

using System;

public class Car
{
  public delegate void FireHandler();
  public event FireHandler Fire;

  private int speed;
  public int Speed{
    get { return speed; }
  }

  private DateTime lastTime;
  private double lastPosition;
  public double Position
  {
    get
    {
      return lastPosition 
        + (DateTime.Now - lastTime).TotalSeconds * speed;
    }
  }

  public Car()
  {
    speed = 0;
    lastPosition = 0;
  }

  public void Stop()
  {
    lastPosition += (DateTime.Now - lastTime).TotalSeconds * speed;
    speed = 0;
    Console.WriteLine("Car is stoping...");
  }

  public void Run()
  {
    if(speed != 0)
      return;
    else
    {
      speed = 10;
      lastTime = DateTime.Now;
    }
    Console.WriteLine("Car is running...");
  }

  public void GearUp()
  {
    if(speed == 0)
      return;

    lastPosition += (DateTime.Now - lastTime).TotalSeconds * speed;
    lastTime = DateTime.Now;
    speed += 10;
    if(speed > 100)
    {
      if(Fire != null)
        Fire();
      else
        throw new Exception("The car is on fire...");
    }
  }

  public void GearDown()
  {
    if(speed == 0)
      return;

    lastPosition += (DateTime.Now - lastTime).TotalSeconds * speed;
    lastTime = DateTime.Now;
    speed -= 10;
    if(speed < 0)
      speed = 0;
  }
}