状态模式

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

public class StateDesignMode01 : MonoBehaviour
{
    private void Start()
    {
        Context context = new Context();
        context.SetState(new ConcreteStateA(context));
        context.Handle(5);
        context.Handle(20);
    }
}

public class Context
{
    private IState mState;
    public void SetState(IState state)
    {
        mState = state;
    }
    public void Handle(int arg)
    {
        mState.Handle(arg);
    }
}

public interface IState
{
    void Handle(int arg);
}
public class ConcreteStateA : IState
{
    private Context mContext;
    public ConcreteStateA(Context context)
    {
        mContext = context;
    }
    public void Handle(int arg)
    {
        Debug.Log("ConcreteStateA.Handle" + arg);
        if (arg > 10)
        {
            //状态切换到B
            mContext.SetState(new ConcreteStateB(mContext));
        }
    }
}
public class ConcreteStateB : IState
{
    private Context mContext;
    public ConcreteStateB(Context context)
    {
        mContext = context;
    }
    public void Handle(int arg)
    {
        Debug.Log("ConcreteStateB.Handle" + arg);
        if (arg <= 10)
        {
            //状态切换到A
            mContext.SetState(new ConcreteStateA(mContext));
        }
    }
}