IsLetter Method (Char)
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Char.IsLetter Method (Char)

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Indicates whether the specified Unicode character is categorized as a Unicode letter.

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

public static bool IsLetter(
	char c


Type: System.Char
The Unicode character to evaluate.

Return Value

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

This method determines whether a Char is a member of any category of Unicode letter. Unicode letters include the following:

  • Uppercase letters, such as U+0041 (LATIN CAPITAL LETTER A) through U+005A (LATIN CAPITAL LETTER Z), or U+0400 (CYRILLIC CAPITAL LETTER IE WITH GRAVE) through U+042F (CYRILLIC CAPITAL LETTER YA). These characters are members of the UnicodeCategory.UppercaseLetter category.

  • Lowercase letters, such as U+0061 (LATIN SMALL LETTER A) through U+007A (LATIN SMALL LETTER Z), or U+03AC (GREEK SMALL LETTER ALPHA WITH TONOS) through U+03CE (GREEK SMALL LETTER OMEGA WITH TONOS). These characters are members of the UnicodeCategory.LowercaseLetter category.

  • Title case letters, such as U+01C5 (LATIN CAPITAL LETTER D WITH SMALL LETTER Z WITH CARON) or U+1FFC (GREEK CAPITAL LETTER OMEGA WITH PROSGEGRAMMENI). These characters are members of the UnicodeCategory.TitlecaseLetter category.

  • Modifiers, such as U+02B0 (MODIFIER LETTER SMALL H) through U+02C1 (MODIFIER LETTER REVERSED GLOTTAL STOP), or U+1D2C (MODIFIER LETTER CAPITAL A) through U+1D61 (MODIFIER LETTER SMALL CHI). These characters are members of the UnicodeCategory.ModifierLetter category.

  • Other letters, such as U+05D0 (HEBREW LETTER ALEF) through U+05EA (HEBREW LETTER TAV), U+0621 (ARABIC LETTER HAMZA) through U+063A (ARABIC LETTER GHAIN), or U+4E00 (<CJK Ideograph, First>) through U+9FC3 (<CJK Ideograph, Last>). These characters are members of the UnicodeCategory.OtherLetter category.

The following example demonstrates IsLetter.

using System;

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

      outputBlock.Text += Char.IsLetter(ch).ToString() + "\n";          
      outputBlock.Text += Char.IsLetter("sample string", 7).ToString() + "\n";	
   // The example displays the following output:
   //    False
   //    True

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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