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

Entity.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class Entity : MonoBehaviour
{[Header("Knockback info")][SerializeField] protected Vector2 knockbackDirection;//被击打后的速度信息[SerializeField] protected float knockbackDuration;//被击打的时间protected bool isKnocked;//此值通过卡住SetVelocity函数的方式用来阻止当一个角色被攻击时，会乱动的情况[Header("Collision Info")]public Transform attackCheck;//transform类，代表的时物体的位置,用来控制攻击检测的位置public float attackCheckRadius;//检测半径[SerializeField] protected Transform groundCheck;//transform类，代表的时物体的位置,后面会来定位子组件的位置    [SerializeField] protected float groundCheckDistance;[SerializeField] protected Transform wallCheck;//transform类，代表的时物体的位置,后面会来定位子组件的位置    [SerializeField] protected float wallCheckDistance;[SerializeField] protected LayerMask whatIsGround;//LayerMask类，与Raycast配合，https://docs.unity3d.com/cn/current/ScriptReference/Physics.Raycast.html#region 定义Unity组件public Animator anim { get; private set; }//这样才能配合着拿到自己身上的animator的控制权public Rigidbody2D rb { get; private set; }//配合拿到身上的Rigidbody2D组件控制权public EntityFX fx { get; private set; }//拿到EntityFX#endregionpublic int facingDir { get; private set; } = 1;protected bool facingRight = true;//判断是否朝右protected virtual void Awake(){fx = GetComponent<EntityFX>();拿到的组件上的EntityFX控制权anim = GetComponentInChildren<Animator>();//拿到自己子组件身上的animator的控制权rb = GetComponent<Rigidbody2D>();}protected virtual void Start(){}protected virtual void Update(){}public virtual void Damage(){fx.StartCoroutine("FlashFX");//IEnumertor本质就是将一个函数分块执行，只有满足某些条件才能执行下一段代码，此函数有StartCoroutine调用//https://www.zhihu.com/tardis/bd/art/504607545?source_id=1001StartCoroutine("HitKnockback");//调用被击打后产生后退效果的函数Debug.Log(gameObject.name+"was damaged");}protected virtual IEnumerator HitKnockback(){isKnocked = true;//此值通过卡住SetVelocity函数的方式用来阻止当一个角色被攻击时，会乱动的情况rb.velocity = new Vector2(knockbackDirection.x * -facingDir, knockbackDirection.y);yield return new WaitForSeconds(knockbackDuration);isKnocked = false;}//被击打后产生后退效果的函数#region 速度函数Velocitypublic virtual void SetZeroVelocity(){if(isKnocked){return;}rb.velocity = new Vector2(0, 0);}//设置速度为0函数public virtual void SetVelocity(float _xVelocity, float _yVelocity){if(isKnocked)return;此值通过卡住SetVelocity函数的方式用来阻止当一个角色被攻击时，会乱动的情况rb.velocity = new Vector2(_xVelocity, _yVelocity);//将rb的velocity属性设置为对应的想要的二维向量。因为2D游戏的速度就是二维向量FlipController(_xVelocity);//在其他设置速度的时候调用翻转控制器}//控制速度的函数，此函数在其他State中可能会使用，但仅能通过player.SeVelocity调用#endregion#region 翻转函数Flippublic virtual void Flip(){facingDir = facingDir * -1;facingRight = !facingRight;transform.Rotate(0, 180, 0);//旋转函数,transform不需要额外定义，因为他是自带的}//翻转函数public virtual void FlipController(float _x)//目前设置x，目的时能在空中时也能转身{if (_x > 0 && !facingRight)//当速度大于0且没有朝右时，翻转{Flip();}else if (_x < 0 && facingRight){Flip();}}#endregion#region 碰撞函数Collisionpublic virtual bool IsGroundDetected(){return Physics2D.Raycast(groundCheck.position, Vector2.down, groundCheckDistance, whatIsGround);}//通过RayCast检测是否挨着地面,https://docs.unity3d.com/cn/current/ScriptReference/Physics2D.Raycast.html//xxxxxxxx()   => xxxxxxxx  == xxxxxxxxxx() return xxxxxxxxx;public virtual bool IsWallDetected(){return Physics2D.Raycast(wallCheck.position, Vector2.right * facingDir, wallCheckDistance, whatIsGround);}//通过RayCast检测是否挨着地面,https://docs.unity3d.com/cn/current/ScriptReference/Physics2D.Raycast.html//xxxxxxxx()   => xxxxxxxx  == xxxxxxxxxx() return xxxxxxxxx;protected virtual void OnDrawGizmos(){Gizmos.DrawLine(groundCheck.position, new Vector3(groundCheck.position.x, groundCheck.position.y - groundCheckDistance));//绘制一条从 from(前面的) 开始到 to（后面的） 的线。Gizmos.DrawLine(wallCheck.position, new Vector3(wallCheck.position.x + wallCheckDistance, wallCheck.position.y));//绘制一条从 from(前面的) 开始到 to（后面的） 的线。Gizmos.DrawWireSphere(attackCheck.position, attackCheckRadius);//https://docs.unity3d.com/2022.3/Documentation/ScriptReference/Gizmos.DrawWireSphere.html//绘制具有中心和半径的线框球体。}//画图函数#endregion
}

PlayerPrimaryAttack.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class PlayerPrimaryAttackState : PlayerState
{//p38 2.从ground进入private int comboCounter;private float lastTimeAttacked;//距离上一次攻击的时间private float comboWindow = 2;//可以间隔的时间public PlayerPrimaryAttackState(Player _player, PlayerStateMachine _stateMachine, string _animBoolName) : base(_player, _stateMachine, _animBoolName){}public override void Enter(){base.Enter();xInput = 0;//修复攻击乱转的问题if(comboCounter >2||Time.time>comboWindow+lastTimeAttacked)//当计数器超过2和间隔时间大于window时，进入第一个攻击动作{comboCounter = 0;}Debug.Log(comboCounter);player.anim.SetInteger("ComboCounter", comboCounter);//设置animtor里的comboCounter#region 选择攻击方向float attackDir = player.facingDir;if(xInput != 0){attackDir = xInput;}#endregion//使其能改变攻击方向player.SetVelocity(player.attackMovement[comboCounter].x * attackDir, player.attackMovement[comboCounter].y);//给角色初速度，让角色在攻击触发时移动一点stateTimer = .1f;}public override void Exit(){base.Exit();player.StartCoroutine("BusyFor", .15f);comboCounter++;lastTimeAttacked = Time.time;}public override void Update(){base.Update();if(stateTimer<0){player.SetZeroVelocity();}//1.修改移动时攻击时后可以移动的BUG//2.但给了点时间模拟惯性可以动一点if (triggerCalled){stateMachine.ChangeState(player.idleState);}}
}