方法一：

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

public class DataChange : MonoBehaviour {

    public Button StartBtn;
    public Text DataText;
    public int num;
	void Start ()
    {
        num = PlayerPrefs.GetInt("num", num);

        StartBtn.onClick.AddListener(() =>
        {
            num++;
            PlayerPrefs.SetInt("num", num);
        });
	}
	
	
	void Update ()
    {
        DataText.text = num.ToString();
        PlayerPrefs.GetInt("num",num);
	}
}
 

方法二：

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

/// <summary>
/// 點選按鈕人數加一，關閉儲存資料，再次點選時要從存的資料開始加
/// </summary>
public class TestPlayerPrefs : MonoBehaviour {

    private static TestPlayerPrefs instance;
    public int  Count =1;
    public Text CountText; //統計人數Text

    void Awake()
    {
        instance = this;
        Count = 0;
    }
    void Start()
    {
        Count = PlayerPrefs.GetInt("Count", Count);
        CountText.text = "" + PlayerPrefs.GetInt("Count").ToString();

    }
    //記錄人數
    public static TestPlayerPrefs Instance
    {
        get
        {
            if (instance != null) return instance;

            else
            {
                return null;
            }
        }
    }
    //點選按鈕人數加一併儲存
    public void OnClick()
    {
        CountText.text = "" + ++Count;
        Debug.Log(Count);
        PlayerPrefs.SetInt("Count", Count);
    }
}