Unity设计模式之工厂模式

**工厂模式是我们最常用的实例化对象模式了，是用工厂方法代替new操作的一种模式。工厂模式克服了简单工厂模式违背开放-封闭原则的缺点，又保持了封装对象创建过程的优点**
首先是工厂抽象接口，用于具体的工厂类继承

using System;
using AssemblyCSharp;
namespace FactoryPackage
{
    public interface IFactory
    {
        Operation CreateOperation();
    }
}

然后是具体的工厂类

using System;
using AssemblyCSharp;
namespace FactoryPackage
{
    class AddFactory :IFactory  //加法工厂
    {
        public Operation CreateOperation()
        {
            return new OperationAdd ();
        }

    }
    class SubFactory :IFactory //减法工厂
    {
        public Operation CreateOperation()
        {
            return new OperationSub ();
        }

    }

    class MulFactory : IFactory //乘法工厂
    {
        public Operation CreateOperation()
        {
            return new OperationMul ();
        }
    }
    class DivFactory: IFactory //除法工厂
    {
        public Operation CreateOperation()
        {
            return new OperationDiv ();
        }
    }
}

最后是客户端代码

using System;
using UnityEngine;
using AssemblyCSharp;
namespace FactoryPackage
{
    public class Client : MonoBehaviour
    {
        void Start()
        {
            IFactory operFactory = new AddFactory ();
            Operation oper = operFactory.CreateOperation ();

            oper.NumberA = 2;
            oper.NumberB = 5;
            Debug.Log ("Result:"+oper.GetResult ());

        }
    }
}