Single.ToString Method (String)


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Converts the numeric value of this instance to its equivalent string representation, using the specified format.

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

public string ToString(
	string format


Type: System.String

A numeric format string.

Return Value

Type: System.String

The string representation of the value of this instance as specified by format.

Exception Condition

format is invalid.

The ToString(String) method formats a Single value in a specified format by using the conventions of the current culture. If you want to use the default ("G", or general) format or specify a different culture, use the other overloads of the ToString method, as follows:

To use format

For culture

Use the overload

Default ("G") format

Default (current) culture


Default ("G") format

A specific culture


A specific format

A specific culture

ToString(String, IFormatProvider)

The return value can be PositiveInfinitySymbol, NegativeInfinitySymbol, NaNSymbol, or the string representation of the value of the current instance, as specified by format.

The format parameter can be any valid standard numeric format specifier except for D and X, as well as any combination of custom numeric format specifiers. If format is null or an empty string, the return value 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:

By default, the return value only contains 7 digits of precision although a maximum of 9 digits is maintained internally. If the value of this instance has greater than 7 digits, ToString(String) returns PositiveInfinitySymbol or NegativeInfinitySymbol instead of the expected number. If you require more precision, specify format with the "G9" format specification, which always returns 9 digits of precision, or "R", which returns 7 digits if the number can be represented with that precision or 9 digits if the number can only be represented with maximum precision.

The following example defines a numeric value and formats it as a currency value by using the "C" standard numeric format string and as a numeric value to three decimal places by using the "N" standard numeric format string. The result strings are formatted by using the conventions of the en-US culture. For more information on numeric format strings, see Standard Numeric Format Strings and Custom Numeric Format Strings.

using System;

public class Example
   public static void Main()
      Double number = 1764.3789;

      // Format as a currency value.

      // Format as a numeric value with 3 decimal places.
// The example displays the following output:
//       $1,764.38
//       1,764.379

The following example displays several Single values using each of the supported standard numeric format specifiers together with two custom numeric format strings. One of those custom format strings illustrates how to pad a Single value with leading zeros. In converting the numeric values to strings, the example uses the formatting conventions of the en-US culture.

float[] numbers= { 1054.32179F, -195489100.8377F, 1.0437E21F, 
                   -1.0573e-05F };
string[] specifiers = { "C", "E", "e", "F", "G", "N", "P", 
                        "R", "#,000.000", "0.###E-000",
                        "000,000,000,000.00###" };

foreach (float number in numbers)
   Console.WriteLine("Formatting of {0}:", number);
   foreach (string specifier in specifiers)
      Console.WriteLine("   {0,5}: {1}", 
                        specifier, number.ToString(specifier));

// The example displays the following output to the console:
//       Formatting of 1054.32179:
//              C: $1,054.32
//              E: 1.054322E+003
//              e: 1.054322e+003
//              F: 1054.32
//              G: 1054.32179
//              N: 1,054.32
//              P: 105,432.18 %
//              R: 1054.32179
//          #,000.000: 1,054.322
//          0.###E-000: 1.054E003
//          000,000,000,000.00###: 000,000,001,054.322
//       Formatting of -195489100.8377:
//              C: ($195,489,100.84)
//              E: -1.954891E+008
//              e: -1.954891e+008
//              F: -195489100.84
//              G: -195489100.8377
//              N: -195,489,100.84
//              P: -19,548,910,083.77 %
//              R: -195489100.8377
//          #,000.000: -195,489,100.838
//          0.###E-000: -1.955E008
//          000,000,000,000.00###: -000,195,489,100.00
//       Formatting of 1.0437E+21:
//              C: $1,043,700,000,000,000,000,000.00
//              E: 1.043700E+021
//              e: 1.043700e+021
//              F: 1043700000000000000000.00
//              G: 1.0437E+21
//              N: 1,043,700,000,000,000,000,000.00
//              P: 104,370,000,000,000,000,000,000.00 %
//              R: 1.0437E+21
//          #,000.000: 1,043,700,000,000,000,000,000.000
//          0.###E-000: 1.044E021
//          000,000,000,000.00###: 1,043,700,000,000,000,000,000.00
//       Formatting of -1.0573E-05:
//              C: $0.00
//              E: -1.057300E-005
//              e: -1.057300e-005
//              F: 0.00
//              G: -1.0573E-05
//              N: 0.00
//              P: 0.00 %
//              R: -1.0573E-05
//          #,000.000: 000.000
//          0.###E-000: -1.057E-005
//          000,000,000,000.00###: -000,000,000,000.00001 

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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