C how to realize simple factory mode

C# How to implement simple factory mode

This article mainly introduces “C# How to implement simple factory mode ”, In daily operation , I believe a lot of people are C# There are doubts about how to realize the simple factory mode , Xiao Bian consulted all kinds of materials , Sort out simple and easy-to-use operation methods , I hope to answer ”C# How to implement simple factory mode ” Your doubts help ！ Next , Please follow Xiaobian to learn ！

scene ： There is a monster ,HP yes 100, Now warriors can defeat them with weapons , There are three weapons , Every time the wooden sword hits 20 blood , Iron sword every time 50 blood , Vajra sword every time 100 blood , If you want to use the simple factory method , How to design ？

One . What is a simple factory ？

Responsible for creating instances of other classes by specifically defining one class , Instances created usually have a common parent class .

The structure is roughly shown in the figure below ：

Draw the class diagram of the scene

explain ：

• 1.Sword Is a base class , Save the monster's blood volume through one of the fields , Another virtual method is to fight monsters

• 2. There are three specific categories of weapons , Corresponding to wooden sword 、 Iron sword 、 Jin Gangjian , It realizes various logic of attacking monsters

• 3.CreateSwordFactory class , Is a class that instantiates weapons , Through the call of the client , You can pass in the weapon you want to create .

• 4.Program Is the client

Two . Specific code

1.Sword.cs class

namespace SimpleFactory{        public class Sword        {                protected int monsterLife = 100;                public virtual void beat()                {                                        }        }}

2.WoodSword.cs

namespace SimpleFactory{        public class WoodSword : Sword        {                public override void beat()                {                        while (monsterLife > 0)                        {                                base.monsterLife -= 20;                                Console.WriteLine("The Monster is already alive！");                        }                        Console.WriteLine("Excellent!The Monster is dead!");                 }        }}

3.IronSword.cs

namespace SimpleFactory{        public class IronSword:Sword        {                public override void beat()                {                        while (monsterLife > 0)                        {                                base.monsterLife -= 50;                                Console.WriteLine("The Monster is already alive！");                        }                        Console.WriteLine("Excellent!The Monster is dead!");                 }        }}

4.DiamondSword.cs

namespace SimpleFactory{      public class DiamondSword:Sword        {              public override void beat()                {                        while (monsterLife > 0)                        {                                base.monsterLife -= 100;                                Console.WriteLine("The Monster is already alive！");                        }                        Console.WriteLine("Excellent!The Monster is dead!");                 }        }}

5.CreateSwordFactory.cs

namespace SimpleFactory{        public class CreateSwordFactory        {                public static Sword CreateSword(string sword)                {                        Sword s = null;                        switch (sword)                        {                                 case "WoodSword":                                          s = new WoodSword();                                        break;                                case "IronSword":                                          s = new IronSword();                                        break;                                case "DiamondSword":                                          s = new DiamondSword();                                        break;                                default:                                        break;                        }                        return s;                }        }}

6.Program.cs

namespace SimpleFactory{        class Program        {                static void Main(string[] args)                {                        Sword s = CreateSwordFactory.CreateSword("WoodSword");                        s.beat();                        Console.WriteLine("----------------------");                        s=CreateSwordFactory.CreateSword("IronSword");                        s.beat();                        Console.WriteLine("----------------------");                        s = CreateSwordFactory.CreateSword("DiamondSword");                        s.beat();                }        }}

3、 ... and . Operation effect and summary

effect ：

summary ：

Advantages and disadvantages of the simple factory model ：

advantage ： As shown in the figure below , At this time, we add another sword , Then I don't need to modify things in my red area , Just modify CreateSwordFactory.cs This class will do , Then instantiate this class according to the specific sword given by the client . There is no need to know how each sword is created .

shortcoming ： Think too much reliance on factory classes , Simple factory mode is violated “ Open and closed principle ”, It's a violation “ The system is open to expansion , Turn off for changes ” Principles , Because when I add a new sword, I have to modify the factory class , The corresponding factory class needs to be recompiled .

Here we are , About “C# How to implement simple factory mode ” That's the end of my study , I hope we can solve your doubts . The combination of theory and practice can better help you learn , Let's try ！ If you want to continue to learn more related knowledge , Please continue to pay attention to Yisu cloud website , Xiaobian will continue to strive to bring you more practical articles ！