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Char.IsDigit Method (Char)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Indicates whether the specified Unicode character is categorized as a decimal digit.

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

Syntax

'Declaration
Public Shared Function IsDigit ( _
    c As Char _
) As Boolean
public static bool IsDigit(
    char c
)

Parameters

Return Value

Type: System.Boolean
true if c is a decimal digit; otherwise, false.

Remarks

This method determines if a Char is a radix-10 digit. This contrasts with the IsNumber method, which determines if 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.

Valid digits are members of the UnicodeCategory.DecimalDigitNumber category.

Examples

The following example demonstrates IsDigit.


Module Example

   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

      Dim ch8 As Char
      ch8 = "8"c

      outputBlock.Text &= Char.IsDigit(ch8) & vbCrLf                    ' Output: "True"
      outputBlock.Text += String.Format(Char.IsDigit("sample string", 6)) & vbCrLf     ' Output: "False"

   End Sub

End Module
using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      char ch = '8';

      outputBlock.Text += Char.IsDigit(ch) + "\n";          // Output: "True"
      outputBlock.Text += Char.IsDigit("sample string", 7) + "\n";  // Output: "False"
   }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.