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

 ItemObject_Trigger.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class ItemObject_Trigger : MonoBehaviour
{private ItemObject myItemObject => GetComponentInParent<ItemObject>();private void OnTriggerEnter2D(Collider2D collision){if (collision.GetComponent<Player>() != null){myItemObject.PickupItem();}}
}

ItemObject.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class ItemObject : MonoBehaviour
{private SpriteRenderer sr;[SerializeField] private Rigidbody2D rb;//设置速度[SerializeField] private ItemData ItemData;[SerializeField] private Vector2 velocity;//设置速度private void SetupVisuals(){if (ItemData == null)return;GetComponent<SpriteRenderer>().sprite = ItemData.icon;gameObject.name = ItemData.name;}public void SetupItem(ItemData _itemData,Vector2 _velocity)设置实例函数{ItemData = _itemData;rb.velocity = _velocity;//设置速度SetupVisuals();}public void PickupItem()//拾取函数打包{Inventory.instance.AddItem(ItemData);Destroy(gameObject);}
}

ItemDrop.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UIElements;public class ItemDrop : MonoBehaviour
{[SerializeField] private int possibleItemDrop;//设置可能会出现的材料数量[SerializeField] private ItemData[] possibleDrop;private List<ItemData> dropList = new List<ItemData>();[SerializeField] private GameObject dropPrefab;[SerializeField] private ItemData item;public void GenerateDrop()//随机生成物品函数{for(int i = 0;i<possibleDrop.Length;i++)//一个判断可能出现的装备{if(Random.Range(0,100) <= possibleDrop[i].dropChance){dropList.Add(possibleDrop[i]);}       }for (int i = 0; i < possibleItemDrop; i++)//另一个生成可能出现的装备{ItemData randomItem = dropList[Random.Range(0, dropList.Count - 1)];if(possibleItemDrop <= dropList.Count ){dropList.Remove(randomItem);}DropItem(randomItem);}}public void DropItem(ItemData _itemData)//创建实例函数{GameObject newDrop = Instantiate(dropPrefab, transform.position,Quaternion.identity);Vector2 randomVelocity = new Vector2(Random.Range(-5, 5), Random.Range(15, 20));newDrop.GetComponent<ItemObject>().SetupItem(_itemData, randomVelocity);}
}

 EnemyStats.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.WSA;public class EnemyStat : CharacterStats
{private Enemy enemy;private ItemDrop myDropSystem;[Header("Level details")][SerializeField] private int leval = 1;[Range(0f, 1f)]//一个使数值设置成为一定范围的设置[SerializeField] private float percantageModifier = .4f;//设置等级和成长比例public override void DoDamage(CharacterStats _targetStats){base.DoDamage(_targetStats);}protected override void Die(){base.Die();enemy.Die();myDropSystem.GenerateDrop();}protected override void Start(){//改变伤害和生命值//解决初始血量在升级后不满ApplyLevelModifier();enemy = GetComponent<Enemy>();base.Start();myDropSystem = GetComponent<ItemDrop>();}private void ApplyLevelModifier(){Modify(strength);Modify(agility);Modify(intelligence);Modify(vitality);Modify(damage);Modify(critChance);Modify(critPower);Modify(maxHealth);Modify(armor);Modify(evasion);Modify(magicResistance);Modify(fireDamage);Modify(iceDamage);Modify(lightingDamage);}//专门对某个数值进行提升的函数private void Modify(Stat _stat){for(int i =1;i<leval;i++){float modifier = _stat.GetValue() * percantageModifier;_stat.AddModifier(Mathf.RoundToInt(modifier));}}public override void TakeDamage(int _damage){base.TakeDamage(_damage);}
}

ItemData.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public enum ItemType
{Material,Equipment
}[CreateAssetMenu(fileName = "New Item Data", menuName = "Data/Item")]
public class ItemData : ScriptableObject 
{public ItemType itemType;public string itemName;public Sprite icon;//图标[Range(0,100)]public float dropChance;
}