Double.ToString Method (IFormatProvider)
Converts the numeric value of this instance to its equivalent string representation using the specified culture-specific format information.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- provider
-
Type:
System.IFormatProvider
An object that supplies culture-specific formatting information.
Return Value
Type: System.StringThe string representation of the value of this instance as specified by provider.
Implements
IConvertible.ToString(IFormatProvider)The ToString(IFormatProvider) method formats a Double value in the default ("G", or general) format of a specified culture. If you want to specify a different format or culture, use the other overloads of the ToString method, as follows:
To use format | For culture | Use the overload |
|---|---|---|
Default ("G") format | Default (current) | |
A specific format or precision | Default (current) culture | |
A specific format or precision | A specific culture |
The return value can be PositiveInfinitySymbol, NegativeInfinitySymbol, NaNSymbol, or a string of the form:
[sign]integral-digits[.[fractional-digits]][e[sign]exponential-digits]
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.
Element | Description |
|---|---|
sign | A negative sign or positive sign symbol. |
integral-digits | 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. |
fractional-digits | A series of digits specifying the fractional part of the number. |
'e' | A lowercase character 'e', indicating exponential (scientific) notation. |
exponential-digits | 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 instance is formatted with the general numeric format specifier ("G").
The .NET Framework provides extensive formatting support, which is described in greater detail in the following formatting topics:
For more information about numeric format specifiers, see Standard Numeric Format Strings and Custom Numeric Format Strings.
For more information about formatting, see Formatting Types in the .NET Framework.
The provider parameter is an IFormatProvider implementation whose GetFormat method returns a NumberFormatInfo object. Typically, provider is a CultureInfo object or a NumberFormatInfo object. The provider parameter supplies culture-specific information used in formatting. If provider is null, the return value is formatted using the NumberFormatInfo object for the current culture.
The following example displays the string representation of two Double values using CultureInfo objects that represent several different cultures.
Dim value As Double value = -16325.62015 ' Display value using the invariant culture. Console.WriteLine(value.ToString(CultureInfo.InvariantCulture)) ' Display value using the en-GB culture. Console.WriteLine(value.ToString(CultureInfo.CreateSpecificCulture("en-GB"))) ' Display value using the de-DE culture. Console.WriteLine(value.ToString(CultureInfo.CreateSpecificCulture("de-DE"))) value = 16034.125E21 ' Display value using the invariant culture. Console.WriteLine(value.ToString(CultureInfo.InvariantCulture)) ' Display value using the en-GB culture. Console.WriteLine(value.ToString(CultureInfo.CreateSpecificCulture("en-GB"))) ' Display value using the de-DE culture. Console.WriteLine(value.ToString(CultureInfo.CreateSpecificCulture("de-DE"))) ' This example displays the following output to the console: ' -16325.62015 ' -16325.62015 ' -16325,62015 ' 1.6034125E+25 ' 1.6034125E+25 ' 1,6034125E+25
The following example illustrates the use of ToString, taking a String and an IFormatProvider as parameters.
Public Class Temperature Implements IFormattable Public Overloads Function ToString(ByVal format As String, ByVal provider As IFormatProvider) As String _ Implements IFormattable.ToString If Not (format Is Nothing) Then If format.Equals("F") Then Return [String].Format("{0}'F", Me.Value.ToString()) End If If format.Equals("C") Then Return [String].Format("{0}'C", Me.Celsius.ToString()) End If End If Return m_value.ToString(format, provider) End Function ' The value holder Protected m_value As Double Public Property Value() As Double Get Return m_value End Get Set(ByVal Value As Double) m_value = Value End Set End Property Public Property Celsius() As Double Get Return (m_value - 32) / 1.8 End Get Set(ByVal Value As Double) m_value = Value * 1.8 + 32 End Set End Property End Class
Available since 8
.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