Decimal.ToDouble Method

Converts the value of the specified Decimal to the equivalent double-precision floating-point number.

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

public static double ToDouble(
	decimal d
)

Parameters

d
Type: System.Decimal

The decimal number to convert.

Return Value

Type: System.Double
A double-precision floating-point number equivalent to d.

This operation can produce round-off errors because a double-precision floating-point number has fewer significant digits than a Decimal.

The following code example converts Decimal numbers to Double values using ToDouble method.

// Example of the decimal.ToSingle and decimal.ToDouble methods. 
using System;

class DecimalToSgl_DblDemo
{
    static string formatter = "{0,30}{1,17}{2,23}";

    // Convert the decimal argument; no exceptions are thrown. 
    public static void DecimalToSgl_Dbl( decimal argument )
    {
        object SingleValue;
        object DoubleValue;

        // Convert the argument to a float value.
        SingleValue = decimal.ToSingle( argument );

        // Convert the argument to a double value.
        DoubleValue = decimal.ToDouble( argument );

        Console.WriteLine( formatter, argument, 
            SingleValue, DoubleValue );
    }

    public static void Main( )
    {
        Console.WriteLine( "This example of the \n" +
            "  decimal.ToSingle( decimal ) and \n" +
            "  decimal.ToDouble( decimal ) \nmethods " +
            "generates the following output. It \ndisplays " +
            "several converted decimal values.\n" );
        Console.WriteLine( formatter, "decimal argument", 
            "float", "double" );
        Console.WriteLine( formatter, "----------------", 
            "-----", "------" );

        // Convert decimal values and display the results.
        DecimalToSgl_Dbl( 0.0000000000000000000000000001M );
        DecimalToSgl_Dbl( 0.0000000000123456789123456789M );
        DecimalToSgl_Dbl( 123M );
        DecimalToSgl_Dbl( new decimal( 123000000, 0, 0, false, 6 ) );
        DecimalToSgl_Dbl( 123456789.123456789M );
        DecimalToSgl_Dbl( 123456789123456789123456789M );
        DecimalToSgl_Dbl( decimal.MinValue );
        DecimalToSgl_Dbl( decimal.MaxValue );
    }
}

/*
This example of the
  decimal.ToSingle( decimal ) and
  decimal.ToDouble( decimal )
methods generates the following output. It
displays several converted decimal values.

              decimal argument            float                 double
              ----------------            -----                 ------
0.0000000000000000000000000001            1E-28                  1E-28
0.0000000000123456789123456789     1.234568E-11   1.23456789123457E-11
                           123              123                    123
                    123.000000              123                    123
           123456789.123456789     1.234568E+08       123456789.123457
   123456789123456789123456789     1.234568E+26   1.23456789123457E+26
-79228162514264337593543950335    -7.922816E+28  -7.92281625142643E+28
 79228162514264337593543950335     7.922816E+28   7.92281625142643E+28
*/

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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