Convert.ToByte (Char) converts Unicode character to 8-bit unsigned integer.
Class Sample Public Shared Sub Main() Dim chars() As Char = { "a"c, "z"c, ChrW(7), ChrW(1023) } For Each ch As Char in chars Try Dim result As Byte = Convert.ToByte(ch) Console.WriteLine("{0} is converted to {1}.", ch, result) Catch e As OverflowException Console.WriteLIne("Unable to convert u+{0} to a byte.", _ AscW(ch).ToString("X4")) End Try Next End Sub End Class