定义

提供一个接口，用于创建相关或者依赖对象的家族，而不需要明确指定具体类。

UML类图

实现

案例：提供一个创建手机的应用，根据不同的配件类型，生产不同类型的手机（安卓/iPhone）

定义接口

抽象工厂

    public interface MobileFactory
    {
        // 创建CPU
        ACPU CreateCPU();
        // 创建主板
        AMainboard CreateMainboard();
        // 创建外壳
        AShell CreateShell();
    }

CPU

    public abstract class ACPU
    {
        protected string version;

        protected string name;

        public string Version { get => version; }

        public string Name { get => name; }
    }

主板

    public abstract class AMainboard
    {
        protected string name;

        public string Name { get => name;}

    }

外壳

    public abstract class AShell
    {
        protected double screenSize;
        protected string color;
        public double ScreenSize { get=> screenSize; }
        public string Color { get => color; }
    }

具体工厂类

安卓工厂

    public class AndroidFactory : MobileFactory
    {
        public ACPU CreateCPU()
        {
            return new AndroidCPU();
        }

        public AMainboard CreateMainboard()
        {
            return new AndroidMainBoard();
        }

        public AShell CreateShell()
        {
            return new AndroidShell();
        }
    }

IOS工厂

   public class IOSFactory : MobileFactory
    {
        public ACPU CreateCPU()
        {
            return new IOSCPU();
        }

        public AMainboard CreateMainboard()
        {
            return new IOSMainboard();
        }

        public AShell CreateShell()
        {
            return new IOSShell();
        }
    } 

具体零件类（Member）

安卓

    public class AndroidCPU:ACPU
    {
        public AndroidCPU()
        {
            this.name = "Qualcomm";
            this.version = "860";
        }
    }

    public class AndroidMainBoard:AMainboard
    {
        public AndroidMainBoard()
        {
            name = "mainboard for android";
        }
    }

    public class AndroidShell:AShell
    {
        public AndroidShell()
        {
            screenSize = 6.0;
            color = "black";
        }
    }

IOS

    public class IOSCPU:ACPU
    {
        public IOSCPU()
        {
            name = "A";
            version = "13";
        }
    }

    public class IOSMainboard:AMainboard
    {
        public IOSMainboard()
        {
            name = "mainboard for ios";
        }
    }

    public class IOSShell:AShell
    {
        public IOSShell()
        {
            screenSize = 4.7;
            color = "red";
        }
    }

Client

    public class Mobile
    {
        ACPU cpu;
        AMainboard mainboard;
        AShell shell;
        MobileFactory mobileFactory;
        public Mobile(MobileFactory mobileFactory)
        {
            this.mobileFactory = mobileFactory;
        }

        public void Create()
        {
            cpu = mobileFactory.CreateCPU();
            mainboard = mobileFactory.CreateMainboard();
            shell = mobileFactory.CreateShell();

            Console.WriteLine($"The mobile is created,with cpu:{cpu.Name+cpu.Version},mainboard:{mainboard.Name},outshell:{shell.ScreenSize},{shell.Color}");
        }
    }

测试

    class Program
    {
        static void Main(string[] args)
        {
            MobileFactory mobileFactory = new AndroidFactory();
            Mobile android = new Mobile(mobileFactory);
            android.Create();

            mobileFactory = new IOSFactory();
            Mobile iphone = new Mobile(mobileFactory);
            iphone.Create();

            Console.ReadLine();
        }
    }

运行结果

The mobile is created,with cpu:Qualcomm860,mainboard:mainboard for android,outshell:6,black
The mobile is created,with cpu:A13,mainboard:mainboard for ios,outshell:4.7,red