Single.ToString Method
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Converts the numeric value of this instance to its equivalent string representation.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
<SecuritySafeCriticalAttribute> _
Public Overrides Function ToString As String
[SecuritySafeCriticalAttribute]
public override string ToString()
Return Value
Type: System.String
The string representation of the value of this instance.
Remarks
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 following table describes each element.
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".
.gif "Note") Note: |
|---|
Because the Single data type is not supported on the Macintosh OS X operating system, the string representation of a Single value may be different from those of the other .NET Framework numeric types that are supported by OS X. |
This overload of the ToString method implicitly uses the general numeric format specifier ("G") and the NumberFormatInfo object for the current culture.
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.
Examples
The following example uses the default Single.ToString method to display the string representations of a number of Single values.
' Example for the Single.ToString( ) methods.
Imports System.Globalization
Module Example
Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
Dim singleValue As Single = 11876.54321
Dim format As String = " {0,-30}{1}"
outputBlock.Text &= String.Format("This example of" & vbCrLf & _
" Single.ToString( ), " & vbCrLf & _
" Single.ToString( String )," & vbCrLf & _
" Single.ToString( IFormatProvider ), and " & vbCrLf & _
" Single.ToString( String, IFormatProvider )" & _
vbCrLf & "generates the following output when run in " & _
"the [{0}] culture. " & vbCrLf & "A Single number is " & _
"formatted with various combinations of format " & _
"" & vbCrLf & "strings and IFormatProvider.", _
CultureInfo.CurrentCulture.Name) & vbCrLf
' Format the number without and with format strings.
outputBlock.Text &= String.Format(vbCrLf & "IFormatProvider is not " & _
"used; the default culture is [{0}]:", _
CultureInfo.CurrentCulture.Name) & vbCrLf
outputBlock.Text &= String.Format(format, _
"No format string:", singleValue.ToString()) & vbCrLf
outputBlock.Text &= String.Format(format, _
"'N5' format string:", singleValue.ToString("N5")) & vbCrLf
outputBlock.Text &= String.Format(format, _
"'E' format string:", singleValue.ToString("E")) & vbCrLf
outputBlock.Text &= String.Format(format, _
"'E5' format string:", singleValue.ToString("E5")) & vbCrLf
' Create a CultureInfo object for another culture. Use
' [Dutch - The Netherlands] unless the current culture
' is Dutch language. In that case use [English - U.S.].
Dim cultureName As String = IIf( _
CultureInfo.CurrentCulture.Name.Substring(0, 2) = _
"nl", "en-US", "nl-NL")
Dim culture As New CultureInfo(cultureName)
' Use the CultureInfo object for an IFormatProvider.
outputBlock.Text &= String.Format(vbCrLf & "A CultureInfo object " & _
"for [{0}] is used for the IFormatProvider: ", _
cultureName) & vbCrLf
outputBlock.Text &= String.Format(format, "No format string:", _
singleValue.ToString(culture)) & vbCrLf
outputBlock.Text &= String.Format(format, "'N5' format string:", _
singleValue.ToString("N5", culture)) & vbCrLf
outputBlock.Text &= String.Format(format, "'E' format string:", _
singleValue.ToString("E", culture)) & vbCrLf
' Get the NumberFormatInfo object from CultureInfo, and
' then change the digit group size to 2 and the digit
' separator to '_'.
Dim numInfo As NumberFormatInfo = culture.NumberFormat
numInfo.NumberGroupSizes = New Integer() {2}
numInfo.NumberGroupSeparator = "_"
' Use a NumberFormatInfo object for IFormatProvider.
outputBlock.Text &= String.Format(vbCrLf & _
"A NumberFormatInfo object with digit group " & _
"size = 2 and " & vbCrLf & "digit separator " & _
"= '_' is used for the IFormatProvider:") & vbCrLf
outputBlock.Text &= String.Format(format, "'N' format string:", _
singleValue.ToString("N", culture)) & vbCrLf
outputBlock.Text &= String.Format(format, "'E' format string:", _
singleValue.ToString("E", culture)) & vbCrLf
End Sub
End Module
' This example of
' Single.ToString( ),
' Single.ToString( String ),
' Single.ToString( IFormatProvider ), and
' Single.ToString( String, IFormatProvider )
' generates the following output when run in the [en-US] culture.
' A Single number is formatted with various combinations of format
' strings and IFormatProvider.
'
' IFormatProvider is not used; the default culture is [en-US]:
' No format string: 11876.54
' 'N5' format string: 11,876.54000
' 'E' format string: 1.187654E+004
' 'E5' format string: 1.18765E+004
'
' A CultureInfo object for [nl-NL] is used for the IFormatProvider:
' No format string: 11876,54
' 'N5' format string: 11.876,54000
' 'E' format string: 1,187654E+004
'
' A NumberFormatInfo object with digit group size = 2 and
' digit separator = '_' is used for the IFormatProvider:
' 'N' format string: 1_18_76,54
' 'E' format string: 1,187654E+004
// Example for the Single.ToString( ) methods.
using System;
using System.Globalization;
class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
float singleValue = 11876.54321F;
string format = " {0,-30}{1}";
outputBlock.Text += String.Format("This example of\n" +
" Single.ToString( ), \n" +
" Single.ToString( String ),\n" +
" Single.ToString( IFormatProvider ), and \n" +
" Single.ToString( String, IFormatProvider )\n" +
"generates the following output when run in the [{0}] " +
"culture. \nA Single number is formatted with various " +
"combinations of format \nstrings and IFormatProvider.",
CultureInfo.CurrentCulture.Name) + "\n";
// Format the number without and with format strings.
outputBlock.Text += String.Format("\nIFormatProvider is not " +
"used; the default culture is [{0}]:",
CultureInfo.CurrentCulture.Name) + "\n";
outputBlock.Text += String.Format(format, "No format string:",
singleValue.ToString()) + "\n";
outputBlock.Text += String.Format(format, "'N5' format string:",
singleValue.ToString("N5")) + "\n";
outputBlock.Text += String.Format(format, "'E' format string:",
singleValue.ToString("E")) + "\n";
outputBlock.Text += String.Format(format, "'E5' format string:",
singleValue.ToString("E5")) + "\n";
// Create a CultureInfo object for another culture. Use
// [Dutch - The Netherlands] unless the current culture
// is Dutch language. In that case use [English - U.S.].
string cultureName =
CultureInfo.CurrentCulture.Name.Substring(0, 2) == "nl" ?
"en-US" : "nl-NL";
CultureInfo culture = new CultureInfo(cultureName);
// Use the CultureInfo object for an IFormatProvider.
outputBlock.Text += String.Format("\nA CultureInfo object " +
"for [{0}] is used for the IFormatProvider: ",
cultureName) + "\n";
outputBlock.Text += String.Format(format, "No format string:",
singleValue.ToString(culture)) + "\n";
outputBlock.Text += String.Format(format, "'N5' format string:",
singleValue.ToString("N5", culture)) + "\n";
outputBlock.Text += String.Format(format, "'E' format string:",
singleValue.ToString("E", culture)) + "\n";
// Get the NumberFormatInfo object from CultureInfo, and
// then change the digit group size to 2 and the digit
// separator to '_'.
NumberFormatInfo numInfo = culture.NumberFormat;
numInfo.NumberGroupSizes = new int[] { 2 };
numInfo.NumberGroupSeparator = "_";
// Use a NumberFormatInfo object for IFormatProvider.
outputBlock.Text += String.Format("\nA NumberFormatInfo object with digit " +
"group size = 2 and \ndigit separator = '_' is used " +
"for the IFormatProvider:") + "\n";
outputBlock.Text += String.Format(format, "'N' format string:",
singleValue.ToString("N", culture)) + "\n";
outputBlock.Text += String.Format(format, "'E' format string:",
singleValue.ToString("E", culture)) + "\n";
}
}
/*
This example of
Single.ToString( ),
Single.ToString( String ),
Single.ToString( IFormatProvider ), and
Single.ToString( String, IFormatProvider )
generates the following output when run in the [en-US] culture.
A Single number is formatted with various combinations of format
strings and IFormatProvider.
IFormatProvider is not used; the default culture is [en-US]:
No format string: 11876.54
'N5' format string: 11,876.54000
'E' format string: 1.187654E+004
'E5' format string: 1.18765E+004
A CultureInfo object for [nl-NL] is used for the IFormatProvider:
No format string: 11876,54
'N5' format string: 11.876,54000
'E' format string: 1,187654E+004
A NumberFormatInfo object with digit group size = 2 and
digit separator = '_' is used for the IFormatProvider:
'N' format string: 1_18_76,54
'E' format string: 1,187654E+004
*/
The following code example illustrates the use of the Parse(String) method along with the ToString() method.
Dim Done As Boolean = False
Dim Inp As String
Do
outputBlock.Text &= "Enter a real number: "
Inp = Console.ReadLine()
Try
S = Single.Parse(Inp)
outputBlock.Text &= "You entered " + S.ToString() + "." & vbCrLf
Done = True
Catch E As FormatException
outputBlock.Text &= "You did not enter a number." & vbCrLf
Catch E As Exception
outputBlock.Text &= "An exception occurred while parsing your response: " + E.ToString() & vbCrLf
End Try
Loop While Not Done
bool done = false;
string inp;
do
{
outputBlock.Text += "Enter a real number: ";
inp = Console.ReadLine();
try
{
s = Single.Parse(inp);
outputBlock.Text += String.Format("You entered {0}.", s.ToString()) + "\n";
done = true;
}
catch (FormatException)
{
outputBlock.Text += "You did not enter a number." + "\n";
}
catch (Exception e)
{
outputBlock.Text += String.Format("An exception occurred while parsing your response: {0}", e.ToString()) + "\n";
}
} while (!done);
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.
See Also