C#’s Data Types

v C#’s Data Types

Ø C#’s Value Types

→   For a value type, a variable holds an actual value, such13.13.

→   At the core of C# are the 13 value types shown in Table 3-1. Collectively, these are referred to as the simple types. They are called simple types because they consist of a single value. The simple types are also sometimes referred to as primitive types.

→    NOTE In addition to the simple types, C# defines three other categories of value types. These are enumerations, structures, and null able types, all of which are described later in this book.

§  Integers

→   C# defines nine integer types: char, byte, sbyte, short, ushort, int, uint, long, and ulong. However, the char type is primarily used for representing characters.

→   The remaining eight integer types are used for numeric calculations. Their bit-width and ranges are shown here:

Type	Width in bits	Range	Default value
Bool	8	True or False	False
Byte	8	0 to 255	0
Sbyte	8	-128 to 127	0
Char	16	0 to 128	NULL
Short	16	-32,768 to 32,767	0
Ushort	16	0 to 65,535	0
Int	32	-2,147,483,648 to 2,147,483,647	0
Uint	32	0 to 4,294,967,295	0
Long	64	- 9,223,372,036,854,775,808 to 9,223,372,036,854,775,807	0
Ulong	64	0 to 18,446,744,073,709,551,615	0
Float	32	±1.5 × 10-45 to ±3.4 × 1038	0
Double	64	±5.0 × 10-324 to ±1.7 × 10308	0
Decimal	128	± 1.0 × 10-28 to ± 7.9 × 1028	0

→   C# defines both signed and unsigned versions of the various integer types. The most commonly used integer type is int. If the value you want to store is unsigned, you can use uint. For large signed values, use long. For large unsigned values, use ulong.

→    The smallest integer types are byte and sbyte. Variables of type byte are especially useful when working with raw binary data, such as a byte stream produced by some device. For small signed integers, use sbyte. When you need an integer that is larger than a byte or sbyte, but smaller than an int or uint, use short or ushort.

§  Floating-Point Types

→   The floating-point types can represent numbers that have fractional components. There are two kinds of floating-point types, float and double.

→   The float data type is for smaller floating - point values, for which less precision is required. The double data type is bulkier than the float data type but offers twice the precision (15 digits).

§  Decimal Type

→   The decimal type represents higher - precision floating - point numbers. One of the great things about the CTS and C# is the provision of a dedicated decimal type for financial calculations.