Unity3d 固定一段时间进入某个方法

using UnityEngine;
using System.Collections;
public class NewBehaviourScript : MonoBehaviour {
// Use this for initialization
void Start () {
   InvokeRepeating("LaunchProjectile", 1,5);//1秒后调用LaunchProjectile () 函数，之后每5秒调用一次
}
// Update is called once per frame
void Update () {
   if (Input.GetButton ("Fire")) {
    CancelInvoke();
   }
}
void LaunchProjectile () {
   print("hello");
}
}