unity 利用NavMeshAgent2D实现怪物追人

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;
using UnityEngine.UI;

public class monster : MonoBehaviour
{
    private Transform target;   //设置追踪目标的位置
    public float MoveSpeed = 2.5f; //敌人移动速度
    private NavMeshAgent2D navMeshAgent;  //设置寻路组件
    private Animator animator;//定义一个私密变量动画
    public float guaiwugongjili;

    void Start()
    {
        animator = GetComponent();//获取动画
        target = GameObject.FindWithTag("Player").transform;  //获取游戏中主角的位置，在我的工程里面主角的标签是Player
        navMeshAgent = GetComponent();//获取寻路插件
        navMeshAgent.speed = MoveSpeed;  //设置寻路器的行走速度
        if (navMeshAgent == null)
        {
            navMeshAgent = gameObject.AddComponent();
        }
    }


    void Update()
    {
        navMeshAgent.SetDestination(target.transform.position); //设置寻路目标
        Vector2 input = target.transform.position;
        if (input != Vector2.zero)
        {
            animator.SetBool("AIismove", true);

        }
        else
        {
            animator.SetBool("AIismove", false);
        }

    }
    private void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.tag == "wuqi")
        {
            GameObject.Find("huojuling").GetComponent().TakeDamage(guaiwugongjili);//(Clone)
        }
        if (collision.tag == "Player")
        {
            GameObject.Find("Player").GetComponent().TakeDamage(guaiwugongjili);
        }
    }
   

}