Professional C# 7 and .NET Core 2.0, 7th Edition

10Collections

WHAT’S IN THIS CHAPTER?

• Understanding collection interfaces and types
• Working with lists, queues, and stacks
• Working with linked and sorted lists
• Using dictionaries and sets
• Evaluating performance

WROX.COM CODE DOWNLOADS FOR THIS CHAPTER

The Wrox.com code downloads for this chapter are found at http://www.wrox.com on the Download Code tab. The source code is also available at https://github.com/ProfessionalCSharp/ProfessionalCSharp7 in the directory Collections.

The code for this chapter is divided into the following major examples:

• List Samples
• Queue Sample
• Linked List Sample
• Sorted List Sample
• Dictionary Sample
• Set Sample

OVERVIEW

Chapter 7, “Arrays,” covers arrays and the interfaces implemented by the Array class. The size of arrays is fixed. If the number of elements is dynamic, you should use a collection class instead of an array.

List<T> is a collection class that can be compared to arrays; but there are also other kinds of collections: queues, stacks, linked lists, dictionaries, and sets. The other collection classes have partly different APIs to access the elements in the collection and often a different internal structure for how the items are stored in memory. This chapter covers these collection classes and their differences, including performance differences.

COLLECTION INTERFACES AND TYPES

Most collection classes are in the System.Collections and System.Collections.Generic namespaces. Generic collection classes are located in the