Learning C#

Chapter 5. C# Language Fundamentals

Chapter 2 demonstrates a very simple C# program that prints the text string “Hello world!” to the console screen and provides a line-by-line analysis of that program. However, even that very simple program was complex enough that some of the details had to be skipped over. The current chapter begins an in-depth exploration of the syntax and structure of the C# language.

Types

C# is a strongly typed language. That means that every object you create or use in a C# program must have a specific type (e.g., you must declare the object to be an integer or a string or a Dog or a Button). The type tells the compiler how big the object is and what it can do.

Types come in two flavors: those that are built into the language (intrinsic types) and those you create (classes, structs, and interfaces, discussed in Chapter 8, Chapter 13, and Chapter 14, respectively). C# offers a number of intrinsic types, shown in Table 5-1.

Table 5-1. The intrinsic types

Type	Size (in bytes)	.NET type	Description
byte	1	Byte	Unsigned (values 0-255).
char	2	Char	Unicode characters.
bool	1	Boolean	True or false.
sbyte	1	SByte	Signed (values-128 to 127).
short	2	Int16	Signed (short) (values-32,768 to 32,767).
ushort	2	UInt16	Unsigned (short) (values 0 to 65,535).
int	4	Int32	Signed integer values between -2,147,483,648 and 2,147,483,647.
uint	4	UInt32	Unsigned integer values between 0 and 4,294,967,295.
float	4	Single ...