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Double.ToString Method

Converts the numeric value of this instance to its equivalent string representation.

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

Public Overrides Function ToString As String

Return Value

Type: System.String
The string representation of the value of this instance.

The return value can be PositiveInfinitySymbol, NegativeInfinitySymbol, NaNSymbol, or a string of the form:


Optional elements are framed in square brackets ([ and ]). Elements that contain the term "digits" consist of a series of numeric characters ranging from 0 to 9. The elements listed in the following table are supported.




A negative sign or positive sign symbol.


A series of digits specifying the integral part of the number. Integral-digits can be absent if there are fractional-digits.


A culture-specific decimal point symbol.


A series of digits specifying the fractional part of the number.


A lowercase character 'e', indicating exponential (scientific) notation.


A series of digits specifying an exponent.

Some examples of the return value are "100", "-123,456,789", "123.45e+6", "500", "3.1416", "600", "-0.123", and "-Infinity".

This version of the ToString method implicitly uses the general numeric format specifier ("G") and the NumberFormatInfo for the current culture.

The .NET Framework provides extensive formatting support, which is described in greater detail in the following formatting topics:

The following example uses the default Double.ToString method to display the string representations of a number of Double values.

Dim number As Double

number = 1.6E20
' Displays 1.6E+20.      

number = 1.6E2
' Displays 160.

number = -3.541
' Displays -3.541.

number = -1502345222199E-07
' Displays -150234.5222199.

number = -15023452221990199574E-09
' Displays -15023452221.9902.

number = .60344
' Displays 0.60344.

number = .000000001
' Displays 1E-09.

The following example illustrates the use of ToString.

Dim Done As Boolean = False
Dim Inp As String

    Console.Write("Enter a real number: ")
    inp = Console.ReadLine()
        D = Double.Parse(inp)
        Console.WriteLine("You entered " + D.ToString() + ".")
        Done = True
    Catch e As FormatException
        Console.WriteLine("You did not enter a number.")
    Catch e As ArgumentNullException
       Console.WriteLine("You did not supply any input.")
    Catch e As OverflowException
       Console.WriteLine("The value you entered, {0}, is out of range.", inp)      
    End Try
Loop While Not Done

.NET Framework

Supported in: 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

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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