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Decimal Constructor (Double)

Initializes a new instance of Decimal to the value of the specified double-precision floating-point number.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

'Declaration
Public Sub New ( _
	value As Double _
)
'Usage
Dim value As Double 

Dim instance As New Decimal(value)

Parameters

value
Type: System.Double

The value to represent as a Decimal.

ExceptionCondition
OverflowException

value is greater than MaxValue or less than MinValue.

-or-

value is Double.NaN, Double.PositiveInfinity, or Double.NegativeInfinity.

This constructor rounds value to 15 significant digits using rounding to nearest. This is done even if the number has more than 15 digits and the less significant digits are zero.

The following code example creates several Decimal numbers using the constructor overload that initializes a Decimal structure with a Double value.

' Example of the Decimal( Double ) constructor. 
Imports System
Imports Microsoft.VisualBasic

Module DecimalCtorDoDemo

    ' Get the exception type name; remove the namespace prefix. 
    Function GetExceptionType( ex As Exception ) As String 

        Dim exceptionType   As String = ex.GetType( ).ToString( )
        Return exceptionType.Substring( _
            exceptionType.LastIndexOf( "."c ) + 1 )
    End Function 

    ' Create a Decimal object and display its value. 
    Sub CreateDecimal( value As Double, valToStr As String )

        ' Format and display the constructor.
        Console.Write( "{0,-34}", _
            String.Format( "Decimal( {0} )", valToStr ) )

        ' Construct the Decimal value. 
        Try 
            Dim decimalNum As New Decimal( value )

            ' Display the value if it was created successfully.
            Console.WriteLine( "{0,31}", decimalNum )

        ' Display the exception type if an exception was thrown. 
        Catch ex As Exception
            Console.WriteLine( "{0,31}", GetExceptionType( ex ) )
        End Try 
    End Sub 

    Sub Main( )

        Console.WriteLine( _
            "This example of the Decimal( Double ) constructor " & _
            vbCrLf & "generates the following output." & vbCrLf )
        Console.WriteLine( "{0,-34}{1,31}", "Constructor", _
            "Value or Exception" )
        Console.WriteLine( "{0,-34}{1,31}", "-----------", _
            "------------------" )

        ' Construct Decimal objects from Double values.
        CreateDecimal( 1.23456789E+5, "1.23456789E+5" )                
        CreateDecimal( 1.234567890123E+15, "1.234567890123E+15" )                
        CreateDecimal( 1.2345678901234567E+25, _
            "1.2345678901234567E+25" )
        CreateDecimal( 1.2345678901234567E+35, _
            "1.2345678901234567E+35" )
        CreateDecimal( 1.23456789E-5, "1.23456789E-5" )                
        CreateDecimal( 1.234567890123E-15, "1.234567890123E-15" )      
        CreateDecimal( 1.2345678901234567E-25, _
            "1.2345678901234567E-25" ) 
        CreateDecimal( 1.2345678901234567E-35, _
            "1.2345678901234567E-35" ) 
        CreateDecimal( 1.0 / 7.0, "1.0 / 7.0" ) 
    End Sub  
End Module  

' This example of the Decimal( Double ) constructor 
' generates the following output. 
'  
' Constructor                                    Value or Exception 
' -----------                                    ------------------ 
' Decimal( 1.23456789E+5 )                               123456.789 
' Decimal( 1.234567890123E+15 )                    1234567890123000 
' Decimal( 1.2345678901234567E+25 )      12345678901234600000000000 
' Decimal( 1.2345678901234567E+35 )               OverflowException 
' Decimal( 1.23456789E-5 )                          0.0000123456789 
' Decimal( 1.234567890123E-15 )       0.000000000000001234567890123 
' Decimal( 1.2345678901234567E-25 )  0.0000000000000000000000001235 
' Decimal( 1.2345678901234567E-35 )                               0 
' Decimal( 1.0 / 7.0 )                            0.142857142857143

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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