Working With Data Types

First thing a programmer looks for is what kind of data types a programming languages has and how to use them. In this part, I will cover C# data types and how to use them in a program.

Basic Data Types

Most of the data type in c# are taken from C and C++. This tables lists data types, their description, and a sample example.

Data Type	Description	Example
object	The base type of all types	object obj = null;
string	String type - sequence of Unicode characters	string str = "Mahesh";
sbyte	8-bit signed integral type	sbyte val = 12;
short	16-bit signed integral type	short val = 12;
int	32-bit signed integral type	int val = 12;
long	64-bit signed integral type	long val1 = 12; long val2 = 34L;
bool	Boolean type; a bool value is either true or false	bool val1 = true; bool val2 = false;
char	Character type; a char value is a Unicode character	char val = 'h';
byte	8-bit unsigned integral type	byte val1 = 12; byte val2 = 34U;
ushort	16-bit unsigned integral type	ushort val1 = 12; ushort val2 = 34U;
uint	32-bit unsigned integral type	uint val1 = 12; uint val2 = 34U;
ulong	64-bit unsigned integral type	ulong val1 = 12; ulong val2 = 34U; ulong val3 = 56L; ulong val4 =78UL;
float	Single-precision floating point type	float val = 1.23F;
double	Double-precision floating point type	double val1 = 1.23; double val2 = 4.56D;
decimal	Precise decimal type with 28 significant digits	decimal val= 1.23M;

Types in C#

C# supports two kinds of types: value types and reference types.

Types	Description
Value Types	Includes simple data types such as int, char, bool, enums
Reference Types	Includes object, class, interface, delegate, and array types

Value Types- Value type objects direct contain the actual data in a variables. With value types, the variables each have their own copy of the data, and it is not possible for operations on one to affect the other.

int i = 10;

Reference Types- Reference type variables stores the reference of the actual data. With reference types, it is possible for two variables to reference the same object, and thus possible for operations on one variable to affect the object referenced by the other variable.

MyClass cls1 = new MyClass();

Data Type Conversions

C# supports two types of conversions. Implicit conversions and explicit conversions.

Implicit conversions are direct conversion. For example:

int iVal = 34;
long lVal = intValue;

Explicit conversions includes type casting. conversion. For example:

long lVal = 123456;
int iVal = (int) lVal;