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I have a C# console project I am working on With agetter and no setter

Okay so I am working on a project that haves a abstract public abstract bool IsFull { get; } this is how the school wants me to set it up. I was trying to figure out a work around that but I can't. I have a few files not sure if I want them all to post. so in my class it is inherited from a different class. so when I initiate it from the program cs class I can't get the boolean to change with a simple IsFull = true. I tried IsFull.Equal(true); but read that just a comparison attribute. I will show my code. Remember this is 100% new to me so if you asked questions why don't i do it this way the answer is I never was taught that lol.
So is there a way I can override it within the sweettooth class?
My Ninja class
using System.Collections.Generic;
using IronNinja.Interfaces;
namespace IronNinja.Models
{
abstract class Ninja
{
protected int calorieIntake;
public List<IConsumable> ConsumptionHistory;
public Ninja()
{
calorieIntake = 0;
ConsumptionHistory = new List<IConsumable>();
}
public abstract bool IsFull { get; }
public abstract void Consume(IConsumable item);
}
}
my inherited class sweettooth
using IronNinja.Interfaces;
namespace IronNinja.Models
{
class SweetTooth : Ninja
{
public string Name;
public SweetTooth(string name)
{
Name = name;
}
public override bool IsFull { get; }
public override void Consume(IConsumable item)
{
// provide override for Consume
int sweet = 0;
if (calorieIntake >= 1500)
{
}
else
{
if (item.IsSweet)
{
sweet = 10;
}
ConsumptionHistory.Add(item);
calorieIntake += item.Calories + sweet;
}
item.GetInfo();
}
}
}
Lastly my Programs .cs file
using System;
using IronNinja.Models;
namespace IronNinja
{
class Program
{
static void Main(string[] args)
{
Buffet hungryJack = new Buffet();
SweetTooth Albert = new SweetTooth("Alby");
while (!Albert.IsFull)
{
Albert.Consume(hungryJack.Serve());
}
foreach (Food item in Albert.ConsumptionHistory)
{
Console.WriteLine(item.Name);
System.Console.WriteLine(item.GetInfo());
}
}
}
}

From my understanding, the IsFull property can simply provide the logic to return whether or not the SweetTooth is full:
public override bool IsFull => calorieIntake >= 1500;
And then in SweetTooth.Consume you would check if they are full before consuming more consumables:
public override void Consume(IConsumable item)
{
// provide override for Consume
int sweet = 0;
if (IsFull)
{
return;
}
else
{
if (item.IsSweet)
{
sweet = 10;
}
ConsumptionHistory.Add(item);
calorieIntake += item.Calories + sweet;
}
item.GetInfo();
}

You simply can't, by language design. You can't make your subclass "more permissive" than the parent class.
If you want to assign IsFull property, you have to do it into the SweetTooth class through the constructor. Generally if you set a property with private setter is because you want to manage its state internally and do not let the client code to handle it.
Then, change the SweetTooth constructor as per below:
public SweetTooth(string name, bool isFull)
{
Name = name;
IsFull = isFull;
}
The alternative is to add a private backing field, but again you can edit this only internally:
private bool _isFull;
public override bool IsFull => _isFull;
The Equal method compares two values. In your specific case you called bool.Equals(bool) overload which worked as Albert.IsFull == true

Decorator pattern for a Customer class

Suppose I have a Customer class. A customer can have multiple kinds of loyalty points. For one promotion, the customer may be collecting Rewards. In another, the customer may be collecting Miles. And there is no fixed number of kinds of loyalty points that the Customer is built for. I am sure this is a common use case. Is the decorator pattern a good fit given below sample code?
public interface ICustomer
{
void Display();
}
public class SimpleCustomer : ICustomer
{
public void Display()
{
Console.WriteLine("I am simple customer");
}
}
public abstract class CustomerDecorator : ICustomer
{
protected ICustomer customer;
public CustomerDecorator(ICustomer customer)
{
this.customer = customer ?? throw new ArgumentNullException("customer");
}
public abstract void Display();
}
public class RewardsDecorator : CustomerDecorator
{
private int rewards;
public RewardsDecorator(ICustomer customer, int rewards) : base(customer)
{
this.rewards = rewards;
}
public override void Display()
{
Console.WriteLine("Now I have " + rewards.ToString() + " rewards");
}
}
public class MilesDecorator : CustomerDecorator
{
private int miles;
public MilesDecorator(ICustomer customer, int miles) : base(customer)
{
this.miles = miles;
}
public override void Display()
{
Console.WriteLine("Now I have " + miles.ToString() + " miles");
}
}

Don't think Decorator pattern does what you want it to do. Decorator adds new functionalities on top of the original class. A typical wiki example would say, we can add scroll bar, menu bar, overlays and other UI components on top of canvas. So to make a proper browser window, so you will have:
public class Canvas
public class ScrollableCanvas
public class OverlayedCanvas
etc.
So that we add more functionalities to the original Canvas.
To solve your problem, you should have something like:
public abstract class LoyaltyProgramAccount {...}
public class RewardAccount extends LoyaltyProgramAccount {...}
public class MilesAccount extends LoyaltyProgramAccount {...}
And then add a registery-ish enum:
public enum LoyaltyProgramTypes {
miles,
reward,
}
and then let user be:
public class Customer {
private List<LoyaltyProgramTypes, LoyaltyProgramAccount> accounts;
public void openAccount(LoyaltyProgramTypes type, LoyaltyProgramAccount account) {
accounts.put(type, account);
}
...
}

I do not think that Decorator is the pattern you are looking for.
Besides, your code does not seem to be an implementation of the Decorator pattern. You do not add any functionality to the only function. You just override it. But adding to the existing function is what the Decorator pattern is all about.
My approach would be state / strategy pattern. There are different kinds of rewards. And a customer has one or more of them. These rewards may share a common interface and provide different implementations. The customer (or a subclass or compound object RewardedCustomer) should hold a list or map of these rewards.

I would use the visitor pattern, this is pretty ideal for your situation. This will allow you nicely separate the rewards calculations for you different customer types and run operations against all supported rewards types.
class Program
{
static void Main(string[] args)
{
MilesCustomer customer = new MilesCustomer();
ICustomerVisitor<int> visitor = new MilesCalculation(10);
var miles = customer.Visit(visitor);
visitor = new RewardsCalucation(100);
var rewards = customer.Visit(visitor);
}
}
public interface ICustomerVisitor<T>
{
T Visit(SimpleCustomer cusomter);
T Visit(RewardsCustomer cusomter);
T Visit(MilesCustomer cusomter);
}
public abstract class Customer
{
public Customer()
{
TotalMoneySpent = 10;
}
public int TotalMoneySpent { get; private set; }
public abstract T Visit<T>(ICustomerVisitor<T> visitor);
public virtual void Display()
{
Console.WriteLine("I am simple customer");
}
}
public class RewardsCalucation : ICustomerVisitor<int>
{
private int _rewardsPerDollar;
public RewardsCalucation(int rewardsPerDollar) => _rewardsPerDollar = rewardsPerDollar;
public int Visit(SimpleCustomer cusomter)
{
return 0;
}
public int Visit(RewardsCustomer cusomter)
{
return cusomter.TotalMoneySpent * _rewardsPerDollar;
}
public int Visit(MilesCustomer cusomter)
{
return 0;
}
}
public class MilesCalculation : ICustomerVisitor<int>
{
private int _milesPerDollar;
public MilesCalculation(int milesPerDollar) => _milesPerDollar = milesPerDollar;
public int Visit(SimpleCustomer cusomter)
{
return 0;
}
public int Visit(RewardsCustomer cusomter)
{
return 0;
}
public int Visit(MilesCustomer cusomter)
{
return cusomter.TotalMoneySpent * _milesPerDollar;
}
}
public class SimpleCustomer : Customer
{
public override T Visit<T>(ICustomerVisitor<T> visitor)
{
return visitor.Visit(this);
}
}
public class RewardsCustomer : Customer
{
public override T Visit<T>(ICustomerVisitor<T> visitor)
{
return visitor.Visit(this);
}
}
public class MilesCustomer : Customer
{
public override T Visit<T>(ICustomerVisitor<T> visitor)
{
return visitor.Visit(this);
}
}

class variables and properties with inheritance

I'm confused about properties in C#, espacially with inheritance:
I have a Pokemon class as an example and want the stats to be protected to modify them in the subclasses (for example at level ups) and I want to read the stats from outside.
This would be the verbose way to do it:
// base class
abstract class Pokemon
{
// stats
protected int hp;
public int Hp {
get
{
return hp;
}
protected set
{
hp = value;
}
}
// other stats...
}
My Question is: Is there a short form for this? Something like:
// base class
abstract class Pokemon
{
// stats
public int Kp { get; protected set; }
// other stats...
}
Do these 2 classes work similarly?
I'm confused, because for public getters and setters you write:
// base class
abstract class Pokemon
{
// stats
public int Kp { get; set; }
// other stats...
}
And it works like:
// base class
abstract class Pokemon
{
// stats
private int kp;
public int Kp {
get
{
return kp;
}
set
{
kp = value;
}
}
// other stats...
}
Which one should I prefer?

My Question is: Is there a short form for this?
Yes exactly as you wrote it
Do these 2 classes work similarly?
Yes, in the first example you can additionally manipulate the field hp in the derived classes directly. (personally I don't see the point, you can also make it private )
Which one should I prefer?
That is difficult to say. If you need extra logic to validate the setting of the property use the first option.
private const int maxHP = 3000;
protected int hp;
public int Hp {
get
{
return hp;
}
protected set
{
// extra validation
if(value < maxHP)
hp = value;
else
hp = maxHP;
}
}
if you don't need it, don't use it

Assign multiple values to one object(?)

Note: I am somewhat of a beginner to C#.
I'm working on a little game that will have a bunch of different levels. Each level has its own class that contains variables (and other irrelevant code). Since I need to pass these values to the main class (my form) I have made them all into methods that returns the value I want (since I can't come up with a better solution). example:
class Level01
{
public int Boxes() { return 3; }
public int MaxPoints() { return 46; }
public int Health() { return 63; }
public int[,] SolidBoxes()
{
int[,] position = new int[Boxes(), Boxes()];
position[1, 1] = 1;
return position;
}
}
When I access these values from my form class I do
int boxes;
int maxPoints;
int health;
int[,] solidBoxes;
void readLevelData() //Starts each new level
{
//Reads the correct level
switch (levelNo)
{
case 1:
setValues(Lvl01.Boxes(), Lvl01.MaxPoints(), Lvl01.Health(), Lvl01.SolidBoxes());
break;
//The same case 2:, 3: for Level02,03..
}
}
void setValues(int getBoxes, int getMaxPoints, int getHealth, int[,] getSolidBoxes)
{
boxes = getBoxes;
maxPoints = getMaxPoints;
health = getHealth;
solidBoxes = getSolidBoxes;
}
I am aware that there's probably a million things in my code here that can be done better and I gladly listen if you have any suggestions, but the thing I wish to ask is:
How can I get all the values from each class using maybe just one name? Ex. Instead doing as I do now, is there a way so I can do something similar to this:
case 1:
setValues(Lvl01.Values);
break;
The problem here is in the setValues method, some of the levels has quite a lot of settings that I wish to use, but I doubt the method would want to take like 15 parameters, and I'm not sure what to do when some levels are not using settings that other levels use.
How should I change my code so I do not have to use every single value as a parameter?

You could use a Dictionary<int, Level> to lookup the object representing each level. Instead of the switch/case, you would do something like
Level level = myLevelDictionary[currentLevel];
That requires you change your classes from having one class per level, to one class that represents any level, e.g.:
class Level
{
public int Boxes { get; set; }
public int MaxPoints { get; set; }
public int Health { get; set; }
public int[,] SolidBoxes()
{
int[,] position = new int[boardSize, boardSize];
position[1, 1] = 1;
return position;
}
}
You would then populate your dictionary like
Dictionary<int, Level> myLevelDictionary = new Dictionary<int, Level>()
{
{ 1, new Level() { Boxes = 3, MaxPoints = 46, Health = 63 } },
// etc.
};
UPDATE
A note about abstract classes
You mention abstract classes in your comments. They are useful if all of your levels have some behavior in common, but some have specialized behavior too. They will often be used in games for things that can move in the game, e.g. something like
abstract class Character
{
// Something everyone has
public int HitPoints { get; set; }
// Something everyone does, but does differently
public abstract void Attack(Character target);
}
public class Fighter : Character
{
public int SwordDamage { get; set; }
public void Attack(Character target)
{
target.Damage(this.SwordDamage - target.PhysicalDamageResistance);
}
}
public class Mage : Character
{
public int MagicFireDamage { get; set; }
public int MagicColdDamage { get; set; }
public void Attack(Character target)
{
if (UseFireDamage()) // e.g. roll random chance that the mage uses a fire spell
{
target.Damage(this.SwordDamage - target.FireDamageResistance);
}
else
{
target.Damage(this.SwordDamage - target.ColdDamageResistance);
}
}
}

one way maybe to use a dictionary.
class Level01
{
Dictionary<string,int> values;
public level01()
{
values.Add("Boxes",3);
values.Add("MaxPoints",3);
values.Add("Health",3);
}
//indexer
public int this[string s] {get{return values[s];} set {values[s] = value;}}
}
and use like:
Level01 lv = new Level01();
somemethod(lv["Boxes"]); //passes 3 to some method
although really you would want to use Dictionary<string,object> and add some type checking and other things to make it work smoothly but hopefully you can get started with that

Get an object out of a mixed type collection

Hi I'm new to OOP and I need help on a little problem.
I used a collection called Monsters to store 3 types of object. Spiders, Farmers, Gollum(irrelevant).
My collection as an indexer but when I use it to get an object out of the collection the object is typeless but I really need to TypeCast my next opperation.
private void Form1_Load(object sender, EventArgs e)
{
CurrentOpponent Opponent = new CurrentOpponent();
Gollum myGollum = new Gollum();
AngryFarmer myFarmer = new AngryFarmer();
Ugly_Spider mySpider = new Ugly_Spider();
myMonsters.AddGollum(myGollum);
myMonsters.AddFarmer(myFarmer);
myMonsters.AddUgly(mySpider);
progressBar1.Increment(100);
progressBar2.Increment(100);
Monster myCurrentOpponent = Opponent.randomEncounter();
//textBox1.Text = (this is where i need the type for a cast)myCurrentOpponent.name
}
Here is the randomEncounter where i extract the object
class CurrentOpponent
{
public Monster randomEncounter()
{
Random _random = new Random();
int opp = _random.Next(4);
return myMonsters[opp];
}
And finally the indexer wich returns a monster (parent of all 3 monster types)
public Monster this[int xxx]
{
get
{
return (Monster)List[xxx];
}
}
Help would be really appreciated..!!
Thanks in advance

Ideally, AngryFarmer, Ugly_Spider and Gollum should all inherit from Monster:
public class AngryFarmer : Monster
{
// ...
}
// etc.
You could then just use a List<Monster>:
myMonsters = new List<Monster>();
myMonsters.Add(new AngryFarmer()); // works because AngryFarmer is a kind of Monster
This will allow you to use polymorphism.

you need to use interfaces...... IMonster..... IMonster then has a name
then make all your monsters implement IMonster
and just have a List of IMonsters

you may wanna try it by using interfaces also! have a look...
public interface IMonster
{
String Name { get; }
Int32 Health { get; set; }
}
public class Spider : IMonster
{
public Spider()
{
_health = 100;
}
public string Name
{
get { return "Spider"; }
}
private int _health;
public int Health
{
get { return _health; }
set { _health = value; }
}
}
public class Gollum : IMonster
{
public Gollum()
{
_health = 250;
}
public string Name
{
get { return "Gollum"; }
}
private int _health;
public int Health
{
get { return _health; }
set { _health = value; }
}
}
class Program
{
static void Main(string[] args)
{
List<IMonster> monsters = new List<IMonster>()
{
new Gollum(),
new Spider()
};
IMonster randomMonster = GetRandomMonster(monsters);
Console.WriteLine(randomMonster.Name + "/" + randomMonster.Health);
}
private static IMonster GetRandomMonster(List<IMonster> monsters)
{
//Your code for getting a random monster goes here!
throw new NotImplementedException();
}
}
I like very much this approach... Imagine you have an element on your game that initially is not exactly a monster. Say it is a random element on your game that after a given event it becomes a monster that your Hero (say a game like heroes of mighty and magic) have to fight with. If you decided to add this feature long time after you created the game, it would become harmful/difficult/risky to change it, as this element might have already be inheriting from another class. If you were using interfaces you would simply implement it on this entity and it would promptly be capable of behaving like any other IMonster in your game. It means that this random entity would be able to be passed as a param to the method Fight(IHero hero, IMonster monster);

Ideally, AngryFarmer, Ugly_Spider and Gollum should all inherit
from Monster
I have learn your problem like the problem in the Tetris game:
1/ You have Monsters like I have Shapes.
2/ Each kind of Monster have it own properties (Health, Magic Point,...) and behaviours (attack, run, cast spell,..) like the Blocks have properties (color, position, state,..) and
behaviours (go down, rotate right, rotate left,...)
In the scene of the game you want to random a Monster that have the specific properties and behaviours, like I want to random a Shape. If it is your problem you can try my code:
public abstract class CMonster
{
int _HP;
int _MP;
//..and something like this
public int HP
{
get { return this._HP; }
set { this._HP=value;}
}
public int MP
{
get { return this._MP; }
set { this._MP = value; }
}
public abstract void Run();
public abstract void Attach();
public abstract void CastSpell();
}
public class CUgly_Spider : CMonster
{
public CUgly_Spider()
{
this.MP = 100;//your value here
this.HP = 100;//your value here
}
public override void Attach()
{
//your implemetation here
}
public override void Run()
{
//your implemetation here
}
public override void CastSpell()
{
//your implemetation here
}
}
public class CGollum : CMonster
{
public CGollum()
{
this.MP = 100;//your value here
this.HP = 100;//your value here
}
public override void Attach()
{
//your implemetation here
}
public override void Run()
{
//your implemetation here
}
public override void CastSpell()
{
//your implemetation here
}
}
class Test
{
private void InitTheGame()
{
CMonster curMonster=null;
Random rnd = new Random();
//sample random
if ((rnd.Next() % 2) == 0)
{
curMonster = new CGollum();
}
else
{
curMonster = new CUgly_Spider();
}
curMonster.Run();//when (rnd.Next() % 2) == 0 then the Gollum is doing else the Ugly_Spider
curMonster.Attach();//when (rnd.Next() % 2) == 0 then the Gollum is doing else the Ugly_Spider
curMonster.CastSpell();//when (rnd.Next() % 2) == 0 then the Gollum is doing else the Ugly_Spider
}
}
I hope that can help you.