Alex教程每一P的教程原代码加上我自己的理解初步理解写的注释，可供学习Alex教程的人参考
此代码仅为较上一P有所改变的代码

【Unity教程】从0编程制作类银河恶魔城游戏_哔哩哔哩_bilibili

 GameData.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
[System.Serializable]
public class GameData
{public int currency;public SerializableDictionary<string, bool> skillTree;public SerializableDictionary<string, int> inventory;public List<string> equipmentId;public GameData(){this.currency = 0;skillTree = new SerializableDictionary<string, bool>();inventory = new SerializableDictionary<string, int>();equipmentId = new List<string>();}
}

Skill

using System.Collections;
using System.Collections.Generic;
using System.Threading;
using UnityEngine;public class Skill : MonoBehaviour
{public float cooldown;protected float cooldownTimer;protected Player player;//拿到playerprotected virtual void Start(){player = PlayerManager.instance.player;//拿到playerCheckUnlock();}protected virtual void Update(){cooldownTimer -= Time.deltaTime;}protected virtual void CheckUnlock()//再次打开游戏时读取数据文件后使技能可以使用的函数{}public virtual bool CanUseSkill(){if (cooldownTimer < 0){UseSkill();cooldownTimer = cooldown;return true;}else{Debug.Log("Skill is on cooldown");return false;}}public virtual void UseSkill(){// do some skill thing}//整理能返回最近敌人位置的函数protected virtual Transform FindClosestEnemy(Transform _checkTransform){Collider2D[] colliders = Physics2D.OverlapCircleAll(_checkTransform.position, 25);//找到环绕自己的所有碰撞器float closestDistance = Mathf.Infinity;//正无穷大的表示形式（只读）Transform closestEnemy = null;//https://docs.unity3d.com/cn/current/ScriptReference/Mathf.Infinity.htmlforeach (var hit in colliders){if (hit.GetComponent<Enemy>() != null){float distanceToEnemy = Vector2.Distance(_checkTransform.position, hit.transform.position);//拿到与敌人之间的距离if (distanceToEnemy < closestDistance)//比较距离，如果离得更近，保存这个敌人的位置,更改最近距离{closestDistance = distanceToEnemy;closestEnemy = hit.transform;}}}return closestEnemy;}}

UI_SkillTreeSlot

using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;public class UI_SkillTreeSlot : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler,ISaveManager
{[SerializeField] private int skillCost;[SerializeField] private string skillName;[TextArea][SerializeField] private string skillDescription;[SerializeField] private Color lockedSkillColor;private UI ui;public bool unlocked;//一个表示是否解锁的bool值private Image skillImage;[SerializeField] private UI_SkillTreeSlot[] shouldBeUnlocked;[SerializeField] private UI_SkillTreeSlot[] shouldBeLocked;//应该解锁和不该解锁的Slot组和Imageprivate void OnValidate(){gameObject.name = "SkillTreeSlot_UI - " + skillName;}private void Awake(){GetComponent<Button>().onClick.AddListener(() => UnlockSkillSlot());}private void Start(){skillImage = GetComponent<Image>();skillImage.color = lockedSkillColor;ui = GetComponentInParent<UI>();if (unlocked)skillImage.color = Color.white;}public void UnlockSkillSlot()//一个判断此Skill是否可以解锁的函数{if (PlayerManager.instance.HaveEnoughMoney(skillCost) == false)return;Debug.Log("Slot unlocked");for (int i = 0; i < shouldBeUnlocked.Length; i++){if (shouldBeUnlocked[i].unlocked == false){Debug.Log("Cannot unlock skill");return;}}for (int i = 0; i < shouldBeLocked.Length; i++){if (shouldBeLocked[i].unlocked == true){Debug.Log("Cannot unlock skill");return;}}unlocked = true;skillImage.color = Color.white;}public void OnPointerEnter(PointerEventData eventData){ui.skillToolTip.ShowToolTip(skillDescription, skillName,skillCost.ToString());}public void OnPointerExit(PointerEventData eventData){ui.skillToolTip.HideToolTip();}public void LoadData(GameData _data){if(_data.skillTree.TryGetValue(skillName,out bool value)){unlocked = value;}}public void SaveData(ref GameData _data){if (_data.skillTree.TryGetValue(skillName, out bool value))//这应该是跟clear一样的，但是为什么不直接用clear？//因为clear会调用24次，每一次都把前面保存的删了，最后只剩下一个{_data.skillTree.Remove(skillName);_data.skillTree.Add(skillName, unlocked);}else{_data.skillTree.Add(skillName, unlocked);}//_data.skillTree.Clear();//_data.skillTree.Add(skillName, unlocked);}
}

Dogge_Skill

using UnityEngine;
using UnityEngine.UI;public class Dogge_Skill : Skill
{[Header("Dodge")][SerializeField] private UI_SkillTreeSlot unlockDoggeButton;[SerializeField] private int evasionAmount;public bool doggeUnlocked;[Header("Mirage dodge")][SerializeField] private UI_SkillTreeSlot unlockMirageDoggeButton;public bool dodgemirageUnlocked;protected override void Start(){base.Start();unlockDoggeButton.GetComponent<Button>().onClick.AddListener(UnlockDodge);unlockMirageDoggeButton.GetComponent<Button>().onClick.AddListener(UnlockMirageDogge);}protected override void CheckUnlock(){UnlockDodge();UnlockMirageDogge();}private void UnlockDodge(){if (unlockDoggeButton.unlocked && !doggeUnlocked){player.stats.evasion.AddModifier(evasionAmount);Inventory.instance.UpdateStatsUI();doggeUnlocked = true;}}private void UnlockMirageDogge(){if (unlockMirageDoggeButton.unlocked)dodgemirageUnlocked = true;}public void CreateMirageOnDoDogge(){if (dodgemirageUnlocked)SkillManager.instance.clone.CreateClone(player.transform, Vector3.zero);}
}