Decimal Constructor (Double)

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)

Public Sub New (
	value As Double
)

Parameters

value
Type: System.Double

The value to represent as a Decimal.

Exception Condition
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

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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