Data Types & Type Conversions in C#

Data Type:

Data type is derived from System.ValueType. The value type contains some data. So, before declaring a variable we write the type of the variable and it is called datatype. According to these datatypesthe system allocates memory to the variables. The types of datatypes are:

Data Type

Allocated memory

 

Range

 

int

4 byte

-2,147,483,648 to 2,147,483,647

short

2 byte

-32,768 to 32,767

long

8 byte

-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807

uint

4 byte

0 to 4,294,967,295

ushort

2 byte

0 to 65,535

ulong

8 byte

0 to 18,446,744,073,709,551,615

float

4 byte

-3.4 x 1038 to + 3.4 x 1038

double

8 byte

(+/-)5.0 x 10-324 to (+/-)1.7 x 10308

decimal

16 byte

(-7.9 x 1028 to 7.9 x 1028) / 100 to 28

byte

1 byte

0 to 255

sbyte

1 byte

-128 to 127

char

16-bit Unicode character

U +0000 to U +ffff

string

A string of Unicode characters.

 

bool

1 byte

True or false

Examples of data types:

  • int a=23; //Allocated 4 bytes
  • float c= 3.45; //Allocated 4 bytes
  • decimal d=0.555555555; // Allocated 16 bytes
  • bool h= true;
  • char c =’A’;
  • string greetings =”Hi all”;
  • double = 4.33333365; // Allocated 8 bytes
  • short = 2; // Allocated 2 bytes

Type Conversion:

Data type can be converted into similar types. And this conversion is called casting. It is of two types. They are:

  1. Implicit casting:

    Data types can be converted implicitly as well as explicitly. Implicitly, the conversion is done by the compiler but there is threat of losing data. It is also called implicit casting. In implicit casting, no external cast function is written.

    Example:

    Int x;
    Double y= x;

    Here, x is integer in start but it is changed into double without writing any casting function.

  2. Explicit casting:

    Explicitly, the conversion is done by using casting to avoid threat of losing data. In explicit casting, external predefined function is written. They need a cast operator.

    Example:

    double y = 123;
    int x = (int)y;

    Here, y is double in start but it is explicitly changed into integer by writing cast function.

There are different type Conversion methods. They are,

1

ToBoolean

Converts a type to a Boolean value, where possible.

2

ToByte

Converts a type to a byte.

3

ToChar

Converts a type to a single Unicode character, where possible.

4

ToDateTime

Converts a type (integer or string type) to date-time structures.

5

ToDecimal

Converts a floating point or integer type to a decimal type.

6

ToDouble

Converts a type to a double type.

7

ToInt16

Converts a type to a 16-bit integer.

8

ToInt32

Converts a type to a 32-bit integer.

9

ToInt64

Converts a type to a 64-bit integer.

10

ToSbyte

Converts a type to a signed byte type.

11

ToSingle

Converts a type to a small floating point number.

12

ToString

Converts a type to a string.

13

ToType

Converts a type to a specified type.

14

ToUInt16

Converts a type to an unsigned int type.

15

ToUInt32

Converts a type to an unsigned long type.

16

ToUInt64

Converts a type to an unsigned big integer.

Example:

  1. using System;    
  2. namespace TypeConversionApplication      
  3. {    
  4.       class StringConversion    
  5.     {    
  6.          static void Main(string[] args)    
  7.          {    
  8.              int i = 5;    
  9.             float f = 53.0 f;    
  10.             double d = 235.75442;    
  11.             bool b = true;    
  12.             Console.WriteLine(i.ToString());    
  13.             Console.WriteLine(f.ToString());    
  14.             Console.WriteLine(d.ToString());    
  15.             Console.WriteLine(b.ToString());    
  16.             Console.ReadKey();    
  17.         }    
  18.     }    

After execution the output generated will be:

5
53.0
235.75442
True

I hope this blog will help you in learning data types and their conversion. Please do comment and give your valuable feedback if needed.
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