Class's instance variables can't be called?

Question

public class Player
{
    private string Name;
    private int Health = 100;
    private int Damage;

    public Player(string name, int health, int damage)
    {
        name = Name;
        health = Health;
        damage = Damage;
    }        
}

public class Enemy
{
    public void enemyTakeDamage()
    {
        int takenDamage;            
    }

    private string Name;
    private int Health = 100;
    private int Damage;
    public string enemyMessages;

    public Enemy(string name, int health, int damage)
    {
        name = Name;
        health = Health;
        damage = Damage;
    }        
}

class Program
{
    static void Main(string[] args)
    {
        bool dead;
        Player P1 = new Player("Zach", 100, 20);               
    }            
}

So I initialized an object called P1 with the name of "zach" and the hp of 100 and damage of 20, I cannot access those 3 variables elsewhere. These arent the private variables in the player class, Im talking about the ones in the class that are intialized by doing :

public Player(string name, int health, int damage)

I thought I can just call P1.health anywhere I wanted if it is public? any help is appreciated and this is my first text based console game I'm working on so other input is also appreciated.

That is currently all the code, am I missing something in it? And I'll try referencing thing but how would I go about redefining it? I would prefer to reference it once and then be able to use its variables. — Zach, May 08 '18 at 01:14
Possible duplicate of [Getter and Setter declaration in .NET](https://stackoverflow.com/questions/17881091/getter-and-setter-declaration-in-net) — OneCricketeer, May 08 '18 at 01:16
The fact that your fields are private hides them to external classes. You can either make them public or add getters — OneCricketeer, May 08 '18 at 01:18
Your class and constructor are public, but your class variables are declared private. — Edwin Chua, May 08 '18 at 01:18
@Zeeeee, you should use properties, not fields, and at the bare minimum you need to make them `public` if you want to expose them. — Rufus L, May 08 '18 at 01:19
So I realized from what you guys said that me setting the variables in the class private blocks it but I thought it could take the parameter variables... Now that I fixed that, what can I do to allow the new player (P1) to be initialized and able to be called from any class? just making it public? — Zach, May 08 '18 at 01:29
your Constructor field assignment is the opposite. For ex: it should be: `Name = name`. This means you are assigning the argument in `name` parameter to class' field `Name`. — kurakura88, May 08 '18 at 01:48
Your player and enemy constructors are pretty obviously wrong. You're making no effort to use the instance's properties so I'm not sure what the point of your question is. — ProgrammingLlama, May 08 '18 at 01:48

Adem Catamak · Answer 1 · 2018-05-08T01:56:55.393

If you want to reach properties/fields like p1.Health, you have to change it public.

Secondly, your assignment order is wrong.

Third, you can access p1.Health not p1.health, because Player does not has propert/field which is name health. It is constructor function's parameter name

public class Player
{
    public string Name;
    public int Health = 100;
    public int Damage;

    /* II. way
          public string Name {get;set;}
          public int Health {get;set;} = 100;
          public int Damage {get;set;}
      */

    /* III. way
        private string _name;
        private int _health = 100;
        private int _damage;

        public string Name {get { return _name ; } }
    */

    public Player(string name, int health, int damage)
    {
        Name = name;
        Health = health;
        Damage = damage;
    }
}

public class Enemy
{
    public void enemyTakeDamage()
    {
        int takenDamage;
    }

    private string Name;
    private int Health = 100;
    private int Damage;
    public string enemyMessages;

    public Enemy(string name, int health, int damage)
    {
        Name = name;
        Health = health;
        Damage = damage;
    }
}


public class Program
{
    static void Main(string[] args)
    {
        bool dead;
        Player P1 = new Player("Zach", 100, 20);
        Console.WriteLine("Name : " + P1.Name + Environment.NewLine +
                          "Health : " + P1.Health +Environment.NewLine +
                          "Damage : "+ P1.Damage);

        Console.ReadKey();
    }

    /* static player
    public static Player P1;
    static void Main(string[] args)
    {
       bool dead;
       P1 = new Player("Zach", 100, 20);
       Console.WriteLine("Name : " + P1.Name + Environment.NewLine +
                         "Health : " + P1.Health + Environment.NewLine +
                         "Damage : " + P1.Damage);

       Console.ReadKey();
    }
   */
}

I added everything you posted and also have the initialize command as so: public Player P1 = new Player("Zach", 100, 20); and it still wont show up in another class (btw its located the line under the end of the "main method" — Zach, May 08 '18 at 01:37
Player P1 is only in Main scope. If you'd like to have that player being accessible to anyone, you need to declare that Player P1 as static. — kurakura88, May 08 '18 at 01:51
If you want to reach `properties` it will be like above code. If you want to create `Player` object and use it every where, it should be static like @kurakura88 says. — Adem Catamak, May 08 '18 at 01:54
I tried adding static by doing both the combination "Public Static" And just "static" It let me access it in the main method but still not anywhere else, for an example I would want it be able to be called from the public void enemyTakeDamage() (Inside the "enemy class" )so I can take the players health and subtract it by the enemy's damage number. — Zach, May 08 '18 at 02:01

score 1 · Accepted Answer · answered May 08 '18 at 02:44

Looking at everything, here are the definitions I think you're after:

public class Player
{
    public string Name { get; set; }
    public int Health { get; set; } = 100;
    public int Damage { get; set; }
    public bool IsAlive { get; set; }

    public Player(string name, int health, int damage)
    {
        Name = name;
        Health = health;
        Damage = damage;
        IsAlive = true;
    }

    public void TakeDamageFromEnemy(Enemy enemy)
    {
        if(IsAlive)
        {
            Health -= enemy.Damage;
            if (Health < 0)
            {
                IsAlive = false;
                MessageBox.Show("Player is dead!");
            }
        }
    }

    public void DoDamageToEnemy(Enemy enemy)
    {
        if(enemy.IsAlive)
        {
            enemy.Health -= Damage;
            if (Health < 0)
            {
                IsAlive = false;
            }
        }
    }
}

public class Enemy
{

    private string Name { get; set; }
    private int Health { get; set; }= 100;
    private int Damage { get;  set;}
    public string enemyMessages { get; set; }
    public bool IsAlive { get; set; } 

    public Enemy(string name, int health, int damage)
    {
        Name = name;
        Health = health;
        Damage = damage;
        IsAlive = true;
    }
    //This is likely replaced by the Player's DoDamageToEnemy method.
    public void enemyTakeDamage()
    {
        int takenDamage;
    }   
}


public class Program
{
    static void Main(string[] args)
    {
        Player playerOne = new Player("Zach", 100, 20);
        Enemy enemyOne = new Enemy("Trogg",15,5);
        Enemy enemyTwo = new Enemy("Dragon",1000,50);
        playerOne.TakeDamageFromEnemy(enemyTwo);
        playerOne.TakeDamageFromEnemy(enemyOne);
        playerOne.DoDamageToEnemy(enemyOne);
        playerOne.TakeDamageFromEnemy(enemyTwo);
        Console.ReadLine();
    }
}

Assuming Damage is how much damager a character puts out, then this should work as a combat model. You can Change the Do and Take Damage to Player.DoDamage(Enemy e) and Enemy.DoDamage(Player p) respectively.

Thank you! this is exactly what I want but I just want to make sure of one thing. You have a MessageBox.Show("Player is dead!"); is this just an example of what I can add because It says MessageBox doesnt exist in the current context. Thanks again :D — Zach, May 08 '18 at 02:52
you would need a reference to System.Windows.Forms in your using statements. That being said, yes this is just a good example to get you to the place where you can start really going crazy. I've found having a working first draft of the code helps seeing how to make the code better later. — EntityFrameworkToday, May 08 '18 at 03:22

Class's instance variables can't be called?

2 Answers2