MCSD Programming in C# 2

Question 1

In C#, what is boxing?

Accepted Answer

Converting a value type to a reference type (object)

Answer

Boxing converts a value type to the `object` reference type, storing it on the heap.

Question 2

Which C# feature allows a method to accept a variable number of parameters?

Accepted Answer

params

Answer

The `params` keyword allows a method to accept a variable number of arguments as an array.

Question 3

What is the default value of a bool field in a C# class?

Accepted Answer

false

Answer

Uninitialized bool fields in C# default to `false`.

Question 4

Which interface must a class implement to use it in a `foreach` loop in C#?

Accepted Answer

IEnumerable

Answer

A class must implement `IEnumerable` (or `IEnumerable<T>`) to support `foreach` iteration.

Question 5

What does the `virtual` keyword allow in C#?

Accepted Answer

Allows a method to be overridden in derived classes

Answer

The `virtual` keyword marks a method so that derived classes can override it using the `override` keyword.

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