C# Essentials, 2nd Edition

Chapter 2. C# Language Reference

This chapter walks you through each aspect of the C# language. Many features of C# will be familiar if you have experience with a strongly typed object-oriented language.

Identifiers

Identifiers are names programmers choose for their types, methods, variables, and so on. An identifiermust be a whole word, essentially composed of Unicode characters starting with a letter or underscore. An identifier must not clash with a keyword. As a special case, the @ prefix can be used to avoid such a conflict, but the character isn’t considered part of the identifier that it precedes. For instance, the following two identifiers are equivalent:

Korn
@Korn

C# identifiers are case-sensitive, but for compatibility with other languages, you should not differentiate public or protected identifiers by case alone.

Types

A C# program is written by building new types and leveraging existing types, either those defined in the C# language itself or imported from other libraries. Each type contains a set of data and function members, which combine to form the modular units that are the key building blocks of a C# program.

Type Instances

Generally, you must create instances of a type to use that type. Those data members and function members that require a type to be instantiated are called instance members. Data members and function members that can be used on the type itself are called static members.

Example: Building and Using Types

In this program, we build our own type called ...