1、工厂模式例子原型

只介绍抽象工厂模式，更多可以看参考里大佬的博客。

假如我们需要宝马车，而且不同配置的宝马车需要不同的发动机和空调来组装成骑车。需要由组装后交给客户。

抽象工厂模式UML

抽象工厂模式原型代码

/// <summary>
/// 工厂模式
/// </summary>
public class FactoryMode : MonoBehaviour
{
    private void Start()
    {

        CarFactory car200 = new CarBMW200();
        car200.CreateEngine();
        car200.CreateAircondition();

        CarFactory car300 = new CarBMW300();
        car300.CreateEngine();
        car300.CreateAircondition();
    }
}

/// <summary>
/// 汽车发动机
/// </summary>
public interface CarEngine
{
}
public class CarEngine1: CarEngine
{
    public CarEngine1()
    {
        Debug.Log("制造发动机1型号。");
    }
}
public class CarEngine2 : CarEngine
{
    public CarEngine2()
    {
        Debug.Log("制造发动机2型号。");
    }
}

/// <summary>
/// 汽车空调
/// </summary>
public interface CarAircondition
{
}
public class CarAircondition1 : CarAircondition
{
    public CarAircondition1()
    {
        Debug.Log("制造空调1型号。");
    }
}
public class CarAircondition2 : CarAircondition
{
    public CarAircondition2()
    {
        Debug.Log("制造空调2型号。");
    }
}

/// <summary>
/// 汽车工厂模式
/// </summary>
public interface CarFactory
{
    CarEngine CreateEngine();

    CarAircondition CreateAircondition();
}
public class CarBMW200 : CarFactory
{
    public CarEngine CreateEngine()
    {
        return new CarEngine1();
    }

    public CarAircondition CreateAircondition()
    {
        return new CarAircondition1();
    }
}
public class CarBMW300 : CarFactory
{
    public CarEngine CreateEngine()
    {
        return new CarEngine2();
    }

    public CarAircondition CreateAircondition()
    {
        return new CarAircondition2();
    }
}

2、工厂模式实例

使用Unity时，会很经常的遇到需要加载资源的问题。这时候就特别适合使用工厂模式，在工厂进行资源加载，我们只需要获取工厂加载好的资源就可以了

工厂模式例子代码

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

/// <summary>
/// 工厂模式
/// </summary>
public class FactoryMode : MonoBehaviour
{
    private void Start()
    {
        //获取加载的资源
        GameObject character = FactoryManager.ResourcesAssetFactory.LoadCharacter("Soldier");
        AudioClip audioClip = FactoryManager.ResourcesAssetFactory.LoadAudioClip("yinyue");
        Sprite sprite = FactoryManager.ResourcesAssetFactory.LoadSprite ("tupian");
    }
}
/// <summary>
/// 资源工厂---加载资源
/// </summary>
public interface IAssetFactory
{
    /// <summary>
    /// 加载角色模型
    /// </summary>
    GameObject LoadCharacter(string name);

    /// <summary>
    /// 加载声音Clip资源
    /// </summary>
    AudioClip LoadAudioClip(string name);

    /// <summary>
    /// 加载精灵Sprite图片
    /// </summary>
    Sprite LoadSprite(string name);
}

/// <summary>
/// 从Unity的Resources文件夹中加载
/// </summary>
public class ResourcesLoadAssetFactory : IAssetFactory
{
    //记录资源在Resources文件夹中的路径
    private const string CharacterPath = "Character/";
    private const string AudioClipPath = "AudioClip/";
    private const string SpritePath = "Sprite/";

    public GameObject LoadCharacter(string name)
    {
        return LoadAsset(CharacterPath + name);
    }

    public AudioClip LoadAudioClip(string name)
    {
        AudioClip audioClip = Resources.Load(AudioClipPath + name) as AudioClip;
        if (audioClip == null)
        {
            Debug.LogError("无法加载路径：" + AudioClipPath + name);
            return null;
        }
        return audioClip;
    }

    public Sprite LoadSprite(string name)
    {
        Sprite sprite = Resources.Load(SpritePath + name) as Sprite;
        if (sprite == null)
        {
            Debug.LogError("无法加载路径：" + SpritePath + name);
            return null;
        }
        return sprite;
    }

    private GameObject LoadAsset(string path)
    {
        GameObject go = Resources.Load(path) as GameObject;
        if (go == null)
        {
            Debug.LogError("无法加载路径：" + path);
            return null;
        }
        return go;
    }
}

/// <summary>
/// 从服务器加载---暂时还不会
/// </summary>
public class RemoteAssetFactory : IAssetFactory
{
    public AudioClip LoadAudioClip(string name)
    {
        throw new System.NotImplementedException();
    }

    public GameObject LoadCharacter(string name)
    {
        throw new System.NotImplementedException();
    }

    public Sprite LoadSprite(string name)
    {
        throw new System.NotImplementedException();
    }
}

/// <summary>
/// 工厂管理静态类，方便获取加载的资源
/// </summary>
public static class FactoryManager
{
    private static IAssetFactory mResourcesAssetFactory = null;
    public static IAssetFactory ResourcesAssetFactory
    {
        get
        {
            if (mResourcesAssetFactory == null)
            {
                mResourcesAssetFactory = new ResourcesLoadAssetFactory();
            }
            return mResourcesAssetFactory;
        }
    }
}

3、工厂模式优缺点

三大工厂模式优缺点