Default keyword for generic types in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to assign the default value of type T to the variable.

C Sharp (C#)

T value = [1];

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

Anew

Bdefault

Cnull

Dtypeof

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'new' instead of 'default' for generic types.

Using 'null' which only works for reference types.

The default keyword returns the default value of the generic type T.

2fill in blank

medium

Complete the method to return the default value of generic type T.

C Sharp (C#)

public T GetDefaultValue<T>() {
    return [1];
}

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

Anull

Bnew T()

Ctypeof(T)

Ddefault(T)

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to use 'new T()' which requires a new() constraint.

Returning 'null' which is invalid for value types.

The method returns default(T) which is the default value for type T.

3fill in blank

hard

Fix the error in the code to correctly assign the default value of T.

C Sharp (C#)

T result = [1](T);

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

Adefault

Bnew

Ctypeof

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'new(T)' which is invalid syntax.

Using 'typeof(T)' which returns a Type object, not a value.

The correct syntax to get the default value is default(T).

4fill in blank

hard

Fill both blanks to create a method that returns the default value of T using expression-bodied syntax.

C Sharp (C#)

public T GetDefault<T>() => [1]([2]);

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

Adefault

BT

Cnew

Dtypeof

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the blanks or using 'new' instead of 'default'.

Using 'typeof' which returns a Type object.

The expression-bodied method returns default(T), the default value of type T.

5fill in blank

hard

Fill all three blanks to create a generic method that returns the default value of T and prints its type.

C Sharp (C#)

public T GetAndPrintDefault<T>() {
    T value = [1]([2]);
    Console.WriteLine(typeof([3]));
    return value;
}

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

Adefault

BT

Cnew

Dobject

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'new' instead of 'default' for the value.

Using 'object' instead of 'T' in typeof.

The method assigns default(T) to value, prints the type T, and returns the value.