Hex number (not ASCII hex value) to string in VB.NET

Question

I've tried searching for this, but most people just want to convert hex values into their ASCII equivalents. That's not what I am looking to do.

I'm looking to see if VB.NET has a simple built-in function to do this:

    Private Function NibbleToString(ByVal Nibble As Byte) As String
    Dim retval As String = String.Empty
    Select Case Nibble

        Case &H0
            retval = "0"
        Case &H1
            retval = "1"
        Case &H2
            retval = "2"
        Case &H3
            retval = "3"
        Case &H4
            retval = "4"
        Case &H5
            retval = "5"
        Case &H6
            retval = "6"
        Case &H7
            retval = "7"
        Case &H8
            retval = "8"
        Case &H9
            retval = "9"
        Case &HA
            retval = "A"
        Case &HB
            retval = "B"
        Case &HC
            retval = "C"
        Case &HD
            retval = "D"
        Case &HE
            retval = "E"
        Case &HF
            retval = "F"
    End Select

    Return retval
End Function

Is there a more elegant way to accomplish the same thing as that code?

Answer 1

Use ToString with the X format specifier:

Dim b As Byte = &HA3
Console.WriteLine(b.ToString("X"))    ' displays "A3"

Dim i As Integer = &H12AB89EF
Console.WriteLine(i.ToString("X"))    ' displays "12AB89EF"

And if you did just want to do a nibble at a time for some reason then you could just mask/shift out the various bits of the number beforehand:

Dim b As Byte = &H5E
Console.WriteLine((b And &HF).ToString("X"))    ' displays "E" (low nibble)
Console.WriteLine((b >> 4).ToString("X"))       ' displays "5" (high nibble)

Answer 2

As a function

<FlagsAttribute()> _
Public Enum whichNibble As Integer
    'byte
    '7654 3210
    ' msn  lsn
    lsn = 1
    msn = 2
    both = lsn Or msn
End Enum

Private Function GetNibble(ByVal aByte As Byte, _
                          Optional ByVal whNib As whichNibble = whichNibble.lsn) As String
    Select Case whNib
        Case whichNibble.both
            Return aByte.ToString("X2")
        Case whichNibble.lsn
            Return (aByte And &HF).ToString("X")
        Case whichNibble.msn
            Return ((aByte >> 4) And &HF).ToString("X")
    End Select
End Function