Data types refer to an extensive system used for declaring variables
or functions of different types. The type of a variable determines how
much space it occupies in storage and how the bit pattern stored is
interpreted.
Data Types Available in VB.Net
VB.Net provides a wide range of data types. The following table shows all the data types available:Data Type | Storage Allocation | Value Range |
---|---|---|
Boolean | Depends on implementing platform | True or False |
Byte | 1 byte | 0 through 255 (unsigned) |
Char | 2 bytes | 0 through 65535 (unsigned) |
Date | 8 bytes | 0:00:00 (midnight) on January 1, 0001 through 11:59:59 PM on December 31, 9999 |
Decimal | 16 bytes | 0 through +/-79,228,162,514,264,337,593,543,950,335 (+/-7.9...E+28) with no decimal point; 0 through +/-7.9228162514264337593543950335 with 28 places to the right of the decimal |
Double | 8 bytes | -1.79769313486231570E+308 through -4.94065645841246544E-324, for negative values 4.94065645841246544E-324 through 1.79769313486231570E+308, for positive values |
Integer | 4 bytes | -2,147,483,648 through 2,147,483,647 (signed) |
Long | 8 bytes | -9,223,372,036,854,775,808 through 9,223,372,036,854,775,807(signed) |
Object | 4 bytes on 32-bit platform 8 bytes on 64-bit platform |
Any type can be stored in a variable of type Object |
SByte | 1 byte | -128 through 127 (signed) |
Short | 2 bytes | -32,768 through 32,767 (signed) |
Single | 4 bytes | -3.4028235E+38 through -1.401298E-45 for negative values; 1.401298E-45 through 3.4028235E+38 for positive values |
String | Depends on implementing platform | 0 to approximately 2 billion Unicode characters |
UInteger | 4 bytes | 0 through 4,294,967,295 (unsigned) |
ULong | 8 bytes | 0 through 18,446,744,073,709,551,615 (unsigned) |
User-Defined | Depends on implementing platform | Each member of the structure has a range determined by its data type and independent of the ranges of the other members |
UShort | 2 bytes | 0 through 65,535 (unsigned) |
Example
The following example demonstrates use of some of the types:Module DataTypes Sub Main() Dim b As Byte Dim n As Integer Dim si As Single Dim d As Double Dim da As Date Dim c As Char Dim s As String Dim bl As Boolean b = 1 n = 1234567 si = 0.12345678901234566 d = 0.12345678901234566 da = Today c = "U"c s = "Me" If ScriptEngine = "VB" Then bl = True Else bl = False End If If bl Then 'the oath taking Console.Write(c & " and," & s & vbCrLf) Console.WriteLine("declaring on the day of: {0}", da) Console.WriteLine("We will learn VB.Net seriously") Console.WriteLine("Lets see what happens to the floating point variables:") Console.WriteLine("The Single: {0}, The Double: {1}", si, d) End If Console.ReadKey() End Sub End ModuleWhen the above code is compiled and executed, it produces the following result:
U and, Me declaring on the day of: 12/4/2012 12:00:00 PM We will learn VB.Net seriously Lets see what happens to the floating point variables: The Single:0.1234568, The Double: 0.123456789012346
The Type Conversion Functions in VB.Net
VB.Net provides the following in-line type conversion functions:S.N | Functions & Description |
---|---|
1 |
CBool(expression) Converts the expression to Boolean data type. |
2 |
CByte(expression) Converts the expression to Byte data type. |
3 |
CChar(expression) Converts the expression to Char data type. |
4 |
CDate(expression) Converts the expression to Date data type |
5 |
CDbl(expression) Converts the expression to Double data type. |
6 |
CDec(expression) Converts the expression to Decimal data type. |
7 |
CInt(expression) Converts the expression to Integer data type. |
8 |
CLng(expression) Converts the expression to Long data type. |
9 |
CObj(expression) Converts the expression to Object type. |
10 |
CSByte(expression) Converts the expression to SByte data type. |
11 |
CShort(expression) Converts the expression to Short data type. |
12 |
CSng(expression) Converts the expression to Single data type. |
13 |
CStr(expression) Converts the expression to String data type. |
14 |
CUInt(expression) Converts the expression to UInt data type. |
15 |
CULng(expression) Converts the expression to ULng data type. |
16 |
CUShort(expression) Converts the expression to UShort data type. |
Example:
The following example demonstrates some of these functions:Module DataTypes Sub Main() Dim n As Integer Dim da As Date Dim bl As Boolean = True n = 1234567 da = Today Console.WriteLine(bl) Console.WriteLine(CSByte(bl)) Console.WriteLine(CStr(bl)) Console.WriteLine(CStr(da)) Console.WriteLine(CChar(CChar(CStr(n)))) Console.WriteLine(CChar(CStr(da))) Console.ReadKey() End Sub End ModuleWhen the above code is compiled and executed, it produces the following result:
True -1 True 12/4/2012 1 1
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