CODEWITHSUNDEEP
c#c#-4.0constructorarguments
Olgo
Olgo

Reputation: 35

How do I pass fewer arguments than the base constructor in to a derived constructor?

My situation would be similar to as follows.

public abstract class Mammal{ public Mammal( name, legs ){ ... } }

public class Dog{ public Dog( name, legs ) : base ( name, legs ) { ... } }

I don't want to always do Dog dog = new Dog( "fido", 4 ); I'd rather just have "legs = 4" in the Dog constructor and pass in the name only.

However, whenever I try to leave "legs" out of the constructors, it tells me certain fields are inaccessible due to protection level.

I am using getters and setters, they are all public.

EDIT: Here is one of the original broken classes -

    public Soil(int idNo, string soilName, string prefabName)
: base(idNo, soilName, price, weight, size, madeOf, prefabName, iconName){

            Price = 0;

    Capacity = 1;
    CanHoldSizes = new ContainerSizes[] {ContainerSizes.seed};
    Contents = new Item[Capacity];      
}

Instead of having to put all 8 parameters in to new Soil(), I wanted to just put the 4 in that would be different for each new Soil() and have the constructor set the rest to defaults.

This creates errors such as: "`Item.price' is inaccessible due to its protection level"

Upvotes: 2

Views: 498

Answers (2)

Justin Lessard
Justin Lessard

Reputation: 11941

You can do this

public class Dog
{        
    public Dog(string name) : base ( name, 4) { } 

    //OR this

    public Dog(string name, int legs = 4) : base ( name, legs) { }
}

The first constructors will always create a Mammal with 4 legs.

The second one will allow you to do this new Dog("MyDog") but the compiler will replace this code by new Dog("MyDog",4).

Of course, using the second one, you'll still be able to do this new Dog("MyDog",3), and it'll create a dog with 3 legs.

Upvotes: 6

John Wu
John Wu

Reputation: 52280

I must be missing something. Isn't it as simple as this?

public class Dog
{
    public Dog(string name) : base (name, 4)
    {
    }
}

Upvotes: 3

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