Array holds multiple objects of different classes, how can I call the coresponding method?

Question

I'd like to apologize in advance for the amount of text that follows. I am learning C# and really got stuck on a task thats probably trivial to advanced users, but searching the internet has brought me to no solution:

In my RPG I have an array that's suposed to hold multiple items (Health Potion, Mana Potion, ...). I want the player to choose which one to use and then call the method thats coresponding to the item.

I define the globaly accesible array thats supossed to hold all items:

static class Globals
    {
       
        public static object[] playerItems = new object[1];
}

Then I define the class "Item":

public class Item
    {
        public string itemName;
        public string itemType;
        public int itemValue;  
    }

Then I define the sub-class HealingPotion, which inherits some but not all variables from the item class. I also define the method to use the item:

    public class HealingPotion : Item
    {
        public int healingValue;

        public HealingPotion (string name, string type, int value, int healingV)
        {
            itemName = name;
            itemType = type;
            itemValue = value;
            healingValue = healingV;

             void usePotion()
            {
                Globals.playerCurrentHp = Globals.playerCurrentHp + healingV;

Then I create a first item:

public static void Main()
        {
                       HealingPotion SmallPotion = new HealingPotion("Kleiner Heiltrank", "small potion", 10, 15);

And then, when the player wants to use an item, I have all items listed to him (inside a method):

int numberOfItems = Globals.playerItems.Length;
            for (int i=0 ; i<numberOfItems; i++)
            {
                Console.WriteLine("     ("+i+") "+((Item)Globals.playerItems[i]).itemName);
}

Now this is where I get stuck: How can I call the corresponding method of the object(item) that the player choses to use? In my example, if the player chooses the healing potion out of many different items, how can I automatically call the UsePotion Method that I defined earlier? I guess I can have all methods in all item-subclasses be called the same (e.g.UseItem() ), but that limits me to a single method per item and forces me to call all methods the same name.

Is there a smarter way to call the method that coresponds to the item the player choses to use? Can I "get" the available methods from knowing the object?

There very few examples in this world were you actually want to use an array of object. Sure you can do it, and its in every second remedial example shows it. However its messy, a code smell, and leads to all sorts of runtime problems, What you actually want to do is define an interface or use a base class and strongly type your collections — TheGeneral, Jan 07 '21 at 00:32
Make an interface `IItem` with a method `DoStuff()`, declare the array as `IItem[]` then call `items[i].DoStuff()` — Charlieface, Jan 07 '21 at 01:14
Does this answer your question? [How to create List of open generic type of class?](https://stackoverflow.com/questions/58570948/how-to-create-list-of-open-generic-type-of-classt) and [How to do generic polymorphism on open types in C#?](https://stackoverflow.com/questions/58247604/how-to-do-generic-polymorphism-on-open-types-in-c/58247676) — , Jan 07 '21 at 06:42

Array holds multiple objects of different classes, how can I call the coresponding method?

0 Answers0