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two newbie questions concerning classes and things

This is a discussion on two newbie questions concerning classes and things within the C# Programming forums, part of the General Programming Boards category; Hi. I recently started learning programming (again) and in my practice game that I've been concepting I ran into some ...

  1. #1
    Jnx
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    two newbie questions concerning classes and things

    Hi. I recently started learning programming (again) and in my practice game that I've been concepting I ran into some problems.

    First, I would like to list all existing instances of a certain class. The class is a country in this game, and it's instances are of course Germany, France etc. What I'd want to achieve is that when the player is given a choice, I'd have some handy way of listing his targets, which would be the countries. Doing this manually for every choice and country would be an immense work and produce a lot of hard coding. Is it even possible to do this?

    Second, the country class has methods of course, and I thought that I had partially solved the problem of choosing targets with this trick

    Code:
    Console.WriteLine("Choose target country");
    string plrChoice = Console.ReadLine();
    (plrChoice).sampleAction();
    I thought that that would work but visual studio complains that it's a build error since string doesn't contain blah blah. So is it even possible to have the user fill name for class in code like that?

    Sorry if I'm confusing, just starting out this thing.

    ps. the "game" is just a simple console application

  2. #2
    Jnx
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    Hmm actually if I want the game to list pre-set countries, I can do that with a string array and foreach loop. Tried doing it with a class array but didn't manage. My second question stands though, can I have the player input the name of the instance of country-class that'll have a method called from?

  3. #3
    CSharpener vart's Avatar
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    So just to be sure

    You have some class like

    Code:
    class Test
    {
       void sample();
    }
    And you have a string variable

    Code:
    string className = "Test";
    And you want using variable className to call a method from the class Test?

    This is what you want to do?

    Is method static?

    Because otherwise you need an instance of the class first...
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  4. #4
    Jnx
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    I do have the instances properly spawned in this fashion

    Code:
    Country germany = new Country();
    Country being my class' name. I thought that would actually "name" the instances, and that I could then with some class array and foreach loop make the game display those names as a list. But from what I understand, that isn't possible?

    Normally I can call a method like this

    Code:
    germany.sampleMethod();
    but what I wanted to do was make the user able to choose from which instance a certain method is called. The methods change the class' variables so essentially player is supposed to choose what country their choice affects.

  5. #5
    CSharpener vart's Avatar
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    I would create a dictionary of countries and use name as a key. Then I can use this dictionary to access country by name
    Code:
      countryList["Germany"].sampleMethod();
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  6. #6
    Gawking at stupidity
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    Why not include Name as a property of Country?

    Code:
    class Country
    {
        public string Name { get; private set; }
    
        public Country(string name)
        {
            Name = name;
        }
    
        public override string ToString()
        {
            return Name;
        }
    }
    And then you instantiate it like this:

    Code:
    Country germany = new Country("Germany");
    Now your players can each have their own list of countries:

    Code:
    class Player
    {
        private List<Country> _countries = new List<Country>();
        public List<Country> Countries { get { return _countries; } }
    }
    Now you're looking at some pretty usable classes:

    Code:
    Player player1 = new Player();
    Country germany = new Country("Germany");
    
    player1.Countries.Add(germany);
    
    foreach(Country country in player1.Countries)
        Console.WriteLine(country);
    Mario F. likes this.
    If you understand what you're doing, you're not learning anything.

  7. #7
    (?<!re)tired Mario F.'s Avatar
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    To make it clear, in istme86 suggestion above, overriding the ToString() method is what will greatly facilitate the usage of this class, as is demonstrated in lines 6 and 7 of the last code snippet.
    The programmer’s wife tells him: “Run to the store and pick up a loaf of bread. If they have eggs, get a dozen.”
    The programmer comes home with 12 loaves of bread.


    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

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