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BigInteger.ToString Method (IFormatProvider)

Converts the numeric value of the current BigInteger object to its equivalent string representation by using the specified culture-specific formatting information.

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

public string ToString(
	IFormatProvider provider


Type: System.IFormatProvider
An object that supplies culture-specific formatting information.

Return Value

Type: System.String
The string representation of the current BigInteger value in the format specified by the provider parameter.

The returned string is formatted with the general format specifier ("G").

The ToString(IFormatProvider) method supports 50 decimal digits of precision. That is, if the BigInteger value has more than 50 digits, only the 50 most significant digits are preserved in the output string; all other digits are replaced with zeros.

The provider parameter is an IFormatProvider implementation. Its GetFormat method returns a NumberFormatInfo object that provides culture-specific information about the format of the string returned by this method. If provider is null, the BigInteger value is formatted using the NumberFormatInfo object of the current culture. The only property of the NumberFormatInfo object that controls the string representation of the BigInteger value using the general format specifier is NumberFormatInfo.NegativeSign, which defines the character that represents the negative sign.

The provider parameter can be one of the following:

The following example instantiates a custom NumberFormatInfo object that defines the tilde (~) as a negative sign. The ToString(IFormatProvider) method then uses the custom NumberFormatInfo object to display a negative BigInteger value.

BigInteger number = 9867857831128;
number = BigInteger.Pow(number, 3) * BigInteger.MinusOne;

NumberFormatInfo bigIntegerProvider = new NumberFormatInfo();
bigIntegerProvider.NegativeSign = "~";


.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, 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.