C# List<baseClass> - any way to store inherited classes within, too?

c#, inheritance, list

Solution

In order to access the properties specific to the inherited class, you need to cast to the appropriate concrete class type. So, rather than accessing `inventory[0]`, you need to access `(weapon)inventory[0]`.

Also, if you are performing common tasks that will have different implementations based on the underlying class, such as logging the values to the console (which I realize was done for testing, but is a good example anyway), you should implement an overridable method in the base class.

For example, in the base class:

public virtual void LogProperties()
{
Console.Write("Name: {0}\nValue: {1}\nWeight: {2}\nDiscardable: {3}\nAttack",
            this.Name, this.BValue, this.Weight, this.Discard);
}

And in the weapon class:

public override void LogProperties()
{
Console.Write("Name: {0}\nValue: {1}\nWeight: {2}\nDiscardable: {3}\nAttack: {4}\nDefense: {5}\nSpeed: {6}\nHandedness: {7}",
            this.Name, this.BValue, this.Weight, this.Discard, 
            this.Atk, this.Def, this.Speed, this.Hands);
}

Then, to access this:

inventory[0].LogProperties();

Problem

I am trying to create a simple "inventory" of items, much like in any RPG. I have very basic classes made, which have properties. Anyway, I have a base class of `item` and inheriting from that is `weapon`. `item` has properties (name, value, weight, "important item") that are also used within `weapon`, but `weapon` has extra properties (attack, defense, speed, handedness). I've got the following code (sorry if the readability is horrible): ``` static void Main(string[] args) { List<item> inventory = new List<item>(); inventory.Add(new weapon("Souleater", 4000, 25.50f, false, 75, 30, 1.25f, 2)); //item---------------------------> weapon---------> Console.Write("Name: {0}\nValue: {1}\nWeight: {2}\nDiscardable: {3}\nAttack: {4}\nDefense: {5}\nSpeed: {6}\nHandedness: {7}", inventory[0].Name, inventory[0].BValue, inventory[0].Weight, inventory[0].Discard, inventory[0].Atk, inventory[0].Def, inventory[0].Speed, inventory[0].Hands); Console.ReadLine(); } ``` Basically, what I'm trying to do is add a new `weapon` to the inventory, but the inventory is a `List<item>` type. I went out on a whim hoping that, due to it's inheritance, it'd be accepted. It was, but the properties specific to `weapon` aren't able to be accessed: ('shopSystem.item' does not contain a definition for 'Atk' and no extension method 'Atk' accepting a first argument of type 'shopSystem.item' could be found) So, is there any way to achieve what I was intending here? Have an "inventory" which can store `item` objects, as well as `weapon`, `armour`, `accessory` etc. objects, which inherit from `item`? It is also worth mentioning that I can access all of the desired properties if I declare the following: ``` weapon Foo = new weapon("Sword", 200, 20.00f, false, 30, 20, 1.10f, 1); ``` Many thanks for reading. Here's the `item` and `weapon` classes, if anybody is interested: ``` class item { #region Region: Item Attributes protected string name = ""; protected int baseValue = 0; protected float weight = 0.00f; protected bool noDiscard = false; #endregion public item(string n, int v, float w, bool nd){ name = n; baseValue = v; weight = w; noDiscard = nd;} public string Name{ get{return name;} set{if(value != ""){ name = value;} }//end set } public int BValue{ get{return baseValue;} } public float Weight{ get{return weight;} } public bool Discard{ get{return noDiscard;} } } class weapon : item { #region Region: Weapon Attributes private int atk = 0; private int def = 0; private float speed = 0.00f; private byte hands = 0; #endregion public weapon(string n, int v, float w, bool nd, int a, int d, float s, byte h) : base(n, v, w, nd){ atk = a; def =d; speed = s; hands = h;} public int Atk{ get{return atk;} } public int Def{ get{return def;} } public float Speed{ get{return speed;} } public byte Hands{ get{return hands;} } } ```

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