Char.IsDigit Method (String, Int32)

Indicates whether the character at the specified position in a specified string is categorized as a decimal digit.

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

public static bool IsDigit(
	string s,
	int index
)

Parameters

s
Type: System.String
A string.
index
Type: System.Int32
The position of the character to evaluate in s.

Return Value

Type: System.Boolean
true if the character at position index in s is a decimal digit; otherwise, false.

ExceptionCondition
ArgumentNullException

s is null.

ArgumentOutOfRangeException

index is less than zero or greater than the last position in s.

This method determines whether a Char is a radix-10 digit. This contrasts with IsNumber, which determines whether a Char is of any numeric Unicode category. Numbers include characters such as fractions, subscripts, superscripts, Roman numerals, currency numerators, encircled numbers, and script-specific digits.

Character positions in a string are indexed starting from zero.

Valid digits are members of the UnicodeCategory.DecimalDigitNumber category.

The following code example demonstrates IsDigit.


using System;

public class IsDigitSample {
	public static void Main() {
		char ch = '8';

		Console.WriteLine(Char.IsDigit(ch));					// Output: "True"
		Console.WriteLine(Char.IsDigit("sample string", 7));	// Output: "False"
	}
}


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, 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.
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

ADD
Show:
© 2014 Microsoft