C# Essentials

Conventions Used in This Book

Throughout this book we use these typographic conventions:

Italic

Represents the names of system elements such as directories and files and Internet resources, such as URLs and web documents. Italics is also used for new terms when they are defined and, occasionally, for emphasis in body text.

Constant width

Indicates language constructs such as .NET and application-defined types, namespaces, and functions, as well as keywords, constants, and expressions that should be typed verbatim. Lines of code and code fragments also appear in constant width, as do classes, class members, and XML tags.

Constant width italic

Represents replaceable parameter names or user-provided elements in syntax.

We have included simple grammar specifications for many, but not all, of the language constructs presented in this book. Our intent is not to be comprehensive—for that level of detail you should consult the Microsoft C# Language Reference in the .NET SDK—but rather to provide you with a fast way to understand the grammar of a particular construct and its valid combinations. The XML occurrence operators (?,*, and +) are used to specify more precisely the number of times an element may occur in a particular construct.

x

Indicates x is to be used verbatim (constant width).

x

Indicates x is supplied by the programmer (constant width italic).

x?

Indicates x may occur zero-or-one times.

x*

Indicates x may occur zero-or-more times, separated by commas.

x+

Indicates x may occur one-or-more times, separated by commas.

[... ]

Indicates a logical grouping of code elements, when not implicitly grouped using the verbatim terms {}, ( ), and [].

[ x | y ]

Indicates only one of a choice of code elements may occur.

Tip

This icon designates a note, which is an important aside to the nearby text.

Warning

This icon designates a warning relating to the nearby text.