Interface as contract mental model in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare an interface named IAnimal.

C Sharp (C#)

public interface [1] {
    void Speak();
}

Drag options to blanks, or click blank then click option'

AIAnimal

BAnimal

CInterfaceAnimal

DAnimalInterface

Attempts:

3 left

💡 Hint

Common Mistakes

Using a class name instead of an interface name.

Not starting the interface name with 'I'.

The interface name should start with 'I' by convention, so IAnimal is correct.

2fill in blank

medium

Complete the code to make the Dog class implement the IAnimal interface.

C Sharp (C#)

public class Dog : [1] {
    public void Speak() {
        Console.WriteLine("Woof!");
    }
}

Drag options to blanks, or click blank then click option'

AIDog

BDogInterface

CIAnimal

DAnimal

Attempts:

3 left

💡 Hint

Common Mistakes

Using a class name instead of the interface name after the colon.

Forgetting to implement the interface methods.

The class Dog must implement the interface IAnimal to fulfill the contract.

3fill in blank

hard

Fix the error in the code by completing the interface method declaration.

C Sharp (C#)

public interface IAnimal {
    [1] Speak();
}

Drag options to blanks, or click blank then click option'

Apublic

Bint

Cstring

Dvoid

Attempts:

3 left

💡 Hint

Common Mistakes

Adding 'public' keyword inside interface method declarations.

Using a return type that does not match the implementation.

Interface methods do not have access modifiers and must specify the return type. Here, void means the method returns nothing.

4fill in blank

hard

Fill both blanks to create a dictionary that maps animal names to their sounds using an interface and class.

C Sharp (C#)

Dictionary<string, string> animalSounds = new Dictionary<string, string> {
    {"Dog", [1],
    {"Cat", [2]
};

Drag options to blanks, or click blank then click option'

A"Woof"

B"Meow"

C"Bark"

D"Purr"

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect animal sounds.

Forgetting to put quotes around string values.

The dog sound is "Woof" and the cat sound is "Meow". These strings represent the sounds animals make.

5fill in blank

hard

Fill all three blanks to implement the IAnimal interface in the Cat class with a Speak method.

C Sharp (C#)

public class [1] : [2] {
    public [3] Speak() {
        Console.WriteLine("Meow");
    }
}

Drag options to blanks, or click blank then click option'

ACat

BIAnimal

Cvoid

DAnimal

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong class or interface names.

Incorrect return type in the method declaration.

The class name is Cat, it implements the interface IAnimal, and the Speak method returns void.