使用下面代码可能无法自动销毁
ParticleSystem ptsys = Instantiate (Resources.Load (ptStr, typeof(ParticleSystem))) as ParticleSystem;
ptsys.transform.position = hitPot;
Destroy (ptsys, .65f);
使用下面代码则可以正常销毁
ParticleSystem ptsys = Instantiate (Resources.Load (ptStr, typeof(ParticleSystem))) as ParticleSystem;
ptsys.transform.position = hitPot;
Destroy (ptsys.gameObject, .65f);
其实第一种方法已经删除了粒子系统，只是粒子系统容器是gameObject，如果想完全消除，必须消除gameObject
