Learning C# 3.0

Chapter 14: Generics and Collections

Quiz Solutions

Solution to Question 14-1. Indexers are unnamed. You use the this keyword to create an indexer:

public string this[int index]

Solution to Question 14-2. Any type can be used, although it’s most common to use integers.

Solution to Question 14-3. The elements of the collection that you want to sort must implement IComparable.

Solution to Question 14-4. Generics allow you to create type-safe collections without specifying the type the collection will hold when you create the collection.

Solution to Question 14-5. The IEnumerable<T> interface allows your collection to support a foreach loop.

Solution to Question 14-6. The purpose of the yield keyword is to return a value to the IEnumerator object, within the GetEnumerator( ) method.

Solution to Question 14-7. The size of an array is fixed when you create it. A List<T> expands dynamically when you add more elements.

Solution to Question 14-8. The Capacity property of a List indicates the number of elements that the List has room for. The Capacity is increased automatically when more elements are added.

Solution to Question 14-9. A Stack is a “last-in, first-out” collection, and a Queue is a “first-in, first-out” collection. In a Queue, elements are removed in the same order they were inserted. In a Stack, elements are removed in the opposite order.

Solution to Question 14-10. The key in a Dictionary takes the place of an indexer, and allows you to retrieve the associated value. The key can be ...