BigInteger.ToString Method (String)


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Converts the numeric value of the current BigInteger object to its equivalent string representation by using the specified format.

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

public string ToString(
	string format


Type: System.String

A standard or custom numeric format string.

Return Value

Type: System.String

The string representation of the current BigInteger value in the format specified by the format parameter.

Exception Condition

format is not a valid format string.

The ToString(String) method formats a BigInteger value in a specified format by using a NumberFormatInfo object that represents the conventions of the current culture. If you want to use the "R", or round-trip, format or specify a different culture, use the other overloads of the ToString method, as follows:

To use format

For culture

Use the overload

Round-trip ("R") format

Default (current) culture


Round-trip ("R") format

A specific culture


A specific format

A specific culture

ToString(String, IFormatProvider)

The format parameter can be any valid standard numeric string, or any combination of custom numeric format strings. If format is equal to String.Empty or is null, the return value of the current BigInteger object is formatted with the round-trip format specifier ("R"). If format is any other value, the method throws a FormatException.

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

The format of the returned string is determined by the NumberFormatInfo object for the current culture. Depending on the format parameter, this object controls symbols such as the negative sign, the group separator, and the decimal point symbol in the output string. To provide formatting information for cultures other than the current culture, call the ToString(String, IFormatProvider) overload.

The following example initializes a BigInteger value and displays it by using each standard format string and some custom format strings.

BigInteger value = BigInteger.Parse("-903145792771643190182");
string[] specifiers = { "C", "D", "D25", "E", "E4", "e8", "F0", 
                        "G", "N0", "P", "R", "X", "0,0.000", 
                        "#,#.00#;(#,#.00#)" };

foreach (string specifier in specifiers)
   Console.WriteLine("{0}: {1}", specifier, value.ToString(specifier));

// The example displays the following output:
//       C: ($903,145,792,771,643,190,182.00)
//       D: -903145792771643190182
//       D25: -0000903145792771643190182
//       E: -9.031457E+020
//       E4: -9.0314E+020
//       e8: -9.03145792e+020
//       F0: -903145792771643190182
//       G: -903145792771643190182
//       N0: -903,145,792,771,643,190,182
//       P: -90,314,579,277,164,319,018,200.00 %
//       R: -903145792771643190182
//       X: CF0A55968BB1A7545A
//       0,0.000: -903,145,792,771,643,190,182.000
//       #,#.00#;(#,#.00#): (903,145,792,771,643,190,182.00)

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 4.0
Windows Phone
Available since 8.1
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