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Char.IsLetterOrDigit Method (String, Int32)

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

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

public static bool IsLetterOrDigit(
	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 letter or a decimal digit; otherwise, false.

ExceptionCondition
ArgumentNullException

s is null.

ArgumentOutOfRangeException

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

Character positions in a string are indexed starting from zero.

Valid letters and decimal digits are members of the following categories in UnicodeCategory: UppercaseLetter, LowercaseLetter, TitlecaseLetter, ModifierLetter, OtherLetter, or DecimalDigitNumber.

The following code example demonstrates IsLetterOrDigit.


using System;

public class IsLetterOrDigitSample {
	public static void Main() {
		string str = "newline:\n";

		Console.WriteLine(Char.IsLetterOrDigit('8'));		// Output: "True"
		Console.WriteLine(Char.IsLetterOrDigit(str, 8));	// Output: "False", because it's a newline
	}
}


.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.
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