问粒子系统仅在GetButton()的开始和结束时播放

EN

{
    public float damage = 10f;
    public float range = 100f;
    public float fireRate = 5f;
    public float impactForce = 30f;

    public Camera playerCam;
    public ParticleSystem muzzleFlash;
    public GameObject impactEffect;

    private float nextTimeToFire = 0f;

    // Start is called before the first frame update
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
        if (Input.GetButton("Fire1") && Time.time >= nextTimeToFire)
        {
            nextTimeToFire = Time.time + 1f / fireRate;
            Shoot();
        }
    }

    void Shoot()
    {
        muzzleFlash.Play();

        RaycastHit hit;
        if (Physics.Raycast(playerCam.transform.position, playerCam.transform.forward, out hit, range))
        {
            Debug.Log(hit.transform.name);

            Target target = hit.transform.GetComponent<Target>();
            if (target != null)
            {
                target.TakeDamage(damage);
            }

            if (hit.rigidbody != null)
            {
                hit.rigidbody.AddForce(-hit.normal * impactForce);
            }

            Instantiate(impactEffect, hit.point, Quaternion.LookRotation(hit.normal));
        }
    }
}