IsControl Method (Char)
Collapse the table of content
Expand the table of content

Char.IsControl 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 control character.

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

Public Shared Function IsControl ( _
	c As Char _
) As Boolean


Type: System.Char
A Unicode character.

Return Value

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

Control characters are non-printing and formatting characters, such as ACK, BEL, CR, FF, LF, and VT. The Unicode standard assigns the following code points to control characters: from \U0000 to \U001F, \U007F, and from \U0080 to \U009F. According to the Unicode standard, these values are to be interpreted as control characters unless their use is otherwise defined by an application. Valid control characters are members of the UnicodeCategory.Control category.

The following example lists the Unicode code point of each of the control characters.

Module Example
   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim charsWritten As Integer = 0

      For ctr As Integer = &H0 To &HFFFF
         Dim ch As Char = Convert.ToChar(ctr)

         If Char.IsControl(ch) Then
            outputBlock.Text += String.Format("\U{0:X4}    ", ctr)
            charsWritten += 1
            If (charsWritten Mod 6) = 0 Then
               outputBlock.Text &= vbCrLf
            End If
         End If
   End Sub
End Module
' The example displays the following output:
'       \U0000    \U0001    \U0002    \U0003    \U0004    \U0005
'       \U0006    \U0007    \U0008    \U0009    \U000A    \U000B
'       \U000C    \U000D    \U000E    \U000F    \U0010    \U0011
'       \U0012    \U0013    \U0014    \U0015    \U0016    \U0017
'       \U0018    \U0019    \U001A    \U001B    \U001C    \U001D
'       \U001E    \U001F    \U007F    \U0080    \U0081    \U0082
'       \U0083    \U0084    \U0085    \U0086    \U0087    \U0088
'       \U0089    \U008A    \U008B    \U008C    \U008D    \U008E
'       \U008F    \U0090    \U0091    \U0092    \U0093    \U0094
'       \U0095    \U0096    \U0097    \U0098    \U0099    \U009A
'       \U009B    \U009C    \U009D    \U009E    \U009F

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

© 2017 Microsoft