Unity | 配列の雰囲気(PC閲覧用)

// 0 ~ 4までの5個の番号が付いた、int型の「values」という名前の配列を作成する
int[] values = new int[5];
//配列の「0番に1」,「1番に2」,「2番に3」,「3番に4」,「4番に5」の初期値の入った配列を作成する
int[] values = new int[5]{1, 2, 3, 4, 5};

int value = 2;
int[] values = new int[5];
//valuesの4番目にvalueの値を入れる
values[3] = value;

int value;
int[] values = new int[5];
//０から数えて５番目の値を取りだす
value = values[4]

using UnityEngine;
using TMPro;
namespace BlueBreath.Practice
{
    public class Arr
    {
        private int value = 0;
        public int Value { get => this.value; set => this.value = value;}
        private int[] values;
        public int[] Values { get => this.values; set => this.values = value;}

    }
    public class ArrayDemo : MonoBehaviour
    {
        Arr arr = new Arr();
        // Start is called before the first frame update
        void Start() => ErrObj.SetActive(false);

        // Update is called once per frame
        void Update()
        {
            
        }
        //Slider Text
        [SerializeField] TextMeshProUGUI sliderText;
        [SerializeField] UnityEngine.UI.Slider slider;
        public void SetSliderText() => 
            sliderText?.SetText("{0}",(int)slider?.value);
        //Arr value Text
        [SerializeField] TextMeshProUGUI valueTMPro;
        public void SetArrValue(){
            arr.Value = (int)slider?.value;
            valueTMPro?.SetText("{0}",(int)slider?.value);
        }
        //Arr Values 
        [SerializeField] GameObject[] valueItems = new GameObject[5];
        [SerializeField] TextMeshProUGUI[] valueItemsText = new TextMeshProUGUI[5];
        public void NewArrValues(){
            arr.Values = new int[(int)slider?.value];
            for (int i = 0; i <= 4; i++)
            {
                valueItems[i].SetActive(i <= (int)slider?.value - 1);
                if(i <= (int)slider?.value - 1)valueItemsText[i].SetText("{0}", arr.Values[i]);
            }
        }
        public void SubValsForVal(){
            if((int)slider?.value <= arr.Values.Length - 1){
                arr.Value = arr.Values[(int)slider?.value];
                valueTMPro?.SetText("{0}",arr.Values[(int)slider?.value]);
            }else{
                //IndexOutOfRangeException
                SetActiveErr();
            }
        }
        public void SubValForVals(){
            if((int)slider?.value <= arr.Values.Length - 1){
                arr.Values[(int)slider?.value] = arr.Value;
                valueItemsText[(int)slider?.value].SetText("{0}", arr.Value);
            }else{
                //IndexOutOfRangeException
                SetActiveErr();
            }
        }
        //Show IndexOutOfRangeException
        [SerializeField] GameObject ErrObj;
        public void SetActiveErr(){
            ErrObj.SetActive(true);
            Invoke("SetFalseErr",2);
        }
        public void SetFalseErr() => ErrObj.SetActive(false);
    }
}

slider.value = 5;
values[Slider.value] = value;
//values[5]は6番目の箱で、それは存在しないのでエラーが出ます