SimpleParticlePlayer.cs

using UnityEngine;

public class SimpleParticlePlayer : MonoBehaviour {

    /// <summary>
    /// パーティクルシステムへの参照
    /// </summary>
    [SerializeField]
    ParticleSystem particleSystem;

    /// <summary>
    /// パーティクルを再生するキー
    /// </summary>
    [SerializeField]
    KeyCode playKey = KeyCode.M;

    /// <summary>
    /// パーティクル再生前に前のパーティクルを消去するか？
    /// </summary>
    [SerializeField]
    bool isPlayWithClear = false;
	
	// Update is called once per frame
	void Update () {

        if (Input.GetKeyDown(playKey))
        {
            if (isPlayWithClear)
            {
                particleSystem.Stop();
                particleSystem.Clear();
            }
            particleSystem.Play();
        }
	}
}