private static Image imgEnemyBullet = Resources.bullet;//一样把图先存在字段imgEnemyBullet里
/// <summary>
/// 初始化子弹时要知道的参数是飞机的类型，速度，威力值
/// </summary>
/// <param name="pf"></param>
/// <param name="speed"></param>
/// <param name="power"></param>
public EnemyBullet(PlaneFather pf, int speed, int power) : base(imgEnemyBullet, pf, power, speed, "BULLET-EnemyBullet")
{
//敌机跟机各不同，矫正坐标要在各自的类中改
//这里让敌机的子弹坐标跟着其自己的前面
Y = pf.Y + pf.Height / 2 + 20;
X = pf.X + pf.Width / 2 - 10;
}
/// <summary>
/// 子弹的共有属性，图，所属飞机，速度，名，x坐标，y坐标，高，宽，生命，种类
/// 子弹的x,y坐标与飞机的x,y坐标相绑定，并且有一定的位移偏差，子弹的高与宽都用Image对象的
/// 属性传进去了，生命直接赋给它零
/// </summary>
/// <param name="img"></param>
/// <param name="pf"></param>
/// <param name="power"></param>
/// <param name="speed"></param>
/// <param name="name"></param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="height"></param>
/// <param name="width"></param>
/// <param name="life"></param>
/// <param name="vari"></param>
public Bullet(Image img, PlaneFather pf, int power, int speed, string name)
: base(name, (pf.X + pf.Width / 2), (pf.Y + pf.Height / 2) - 50, img.Height, img.Width, speed, 0, pf.Vari)
{
//把对应的子弹，威力值赋给要实例化的子对象(本机子弹或敌机子弹)
this.BulletImg = img;
this.Power = power;
}
public HeroBullet(PlaneFather pf, int power, int speed) : base(ImgHeroBullect, pf, power, speed * 3, "BestHeroBullet")
{
//由于在继承Bullet已经给本机子弹矫正，这里不需要矫正
}