有关unity3d dictionary的问题

在使用dictionary中，用struct作为Tkey 出现KeyNotFoundException: The given key was not present in the dictionary.问题。
问题代码如下：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;
public class levelManger : MonoBehaviour
{
    // Start is called before the first frame update
    [SerializeField]
    private GameObject[] titlePrefabs;

    [SerializeField]
    private cameraMovement cameraMovement;
    public Dictionary<Point,TitleScript> Tiles {get; set;}
    public float TitleSize
    {
        get{return titlePrefabs[0].GetComponent<SpriteRenderer>().sprite.bounds.size.x;}
    }
    void Start()
    {
        Createlevel();
    }

    // Update is called once per frame
    void Update()
    {

    }
    private void Createlevel()
    {
        Tiles = new Dictionary<Point, TitleScript>();
        string[] mapData = ReadLevelText();
        int mapX = mapData[0].ToCharArray().Length;
        int mapY = mapData.Length;
        Vector3 maxTile =Vector3.zero;
        Vector3 worldStart=Camera.main.ScreenToWorldPoint(new Vector3(0,Screen.height));
        for(int y =0;y<mapY;y++)
        {
            char[] newTitles=mapData[y].ToCharArray();
            for (int x = 0; x < mapX; x++)
            {
            placeTitle(newTitles[x].ToString(),5*x,5*y,worldStart);
            }
        }
   //问题行    _ **maxTile = Tiles[new Point(mapX-1,mapY-1)].transform.position;**_
        cameraMovement.SetLimits(new Vector3(maxTile.x+TitleSize*5,maxTile.y - TitleSize*5));
    }
    private void placeTitle(string titleType,int x,int y,Vector3 worldStart)
    {
        int titleIndex=int.Parse(titleType);
        TitleScript newTitle= Instantiate(titlePrefabs[titleIndex]).GetComponent<TitleScript>();
        newTitle.Setup(new Point(x,y),new Vector3(worldStart.x+(TitleSize * x),worldStart.y-(TitleSize * y),0));
        Tiles.Add(new Point(x,y),newTitle);
    }
    private string[] ReadLevelText()
    {
        TextAsset bindData = Resources.Load("Level") as TextAsset;
        string data = bindData.text.Replace(Environment.NewLine,string.Empty);
        return data.Split('-');
    }
}

public struct Point {
    public int x;
    public int y;
}
public class NewBehaviourScript : MonoBehaviour
{
    public Dictionary<Point, int> dict = new Dictionary<Point, int>();
    void Start()
    {
        dict.Add(new Point { x=1,y=1},1);
        print($"字典结果： {dict[new Point { x = 1, y = 1 }]}");
    }
}

经测试毫无问题，你应检查你输入的Key是否在字典内

看起来应该是你的key真的不存在，建议检查逻辑，或者使用前判断是否存在此key

另外不建议使用复杂类型当做字典的key，建议在Point中重写一下ToString方法，使用其返回值的字符串当做Key，这样基本可以满足需求，