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Char.IsSymbol Method (String, Int32)

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

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

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

Syntax

'Declaration
Public Shared Function IsSymbol ( _
    s As String, _
    index As Integer _
) As Boolean

public static bool IsSymbol(
    string s,
    int index
)

Parameters

Return Value

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

Exceptions

Exception Condition
ArgumentNullException

s is nulla null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException

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

Remarks

Character positions in a string are indexed starting from zero.

Valid symbols are members of the following categories in System.Globalization.UnicodeCategory: MathSymbol, CurrencySymbol, ModifierSymbol, and OtherSymbol.

Symbols in the Unicode standard are a loosely defined set of characters that include the following:

  • Currency symbols.

  • Letterlike symbols, which include a set of mathematical alphanumeric symbols, as well as such symbols as ℅, №, and ™.

  • Number forms, such as subscripts and superscripts.

  • Mathematical operators and arrows.

  • Geometric symbols.

  • Technical symbols.

  • Braille patterns.

  • Dingbats.

Examples

The following example demonstrates IsSymbol.


Module Example

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

      Dim str As String
      str = "non-symbolic characters"

      outputBlock.Text &= Char.IsSymbol("+"c) & vbCrLf      ' Output: "True"
      outputBlock.Text += String.Format(Char.IsSymbol(str, 8)) & vbCrLf    ' Output: "False"

   End Sub

End Module

using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      string str = "non-symbolic characters";

      outputBlock.Text += Char.IsSymbol('+') + "\n";           // Output: "True"
      outputBlock.Text += Char.IsSymbol(str, 8) + "\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.