Convert bytearray (of arbitrary size) to string of arbitrary base

[Arokh]

Hi,

 

My current situation:

After hashing I get a bytearray of 24 bytes,

normally one would just convert it to hex which is easy.

 

But now I have to convert it to the base of 36 (0-9 + A-Z),

which is not so easy anymore.

 

Is there a simple way to do this?

 

The idea I have come up with seems a bit complex for the problem:

[CSharp]public static byte[] ByteMultiply(byte[] b, int x)

public static byte[] ByteDivision(byte[] b, int x)

public static byte[] ByteAdd(byte[] b, int x)

public static byte[] ByteSubstract(byte[] b1, byte[] b2)

public static bool ByteEqual(byte[] b, int x)

public static bool ByteGreaterThan(byte[] b1, byte[] b2)

 

public static string ToString(byte[] b, int baseNumber) {

byte[] baseDigit = new byte[0];

string baseStr = "";

 

baseDigit = ByteAdd(baseDigit, 1);

while(true) {

baseDigit = ByteMultiply(baseDigit, baseNumber);

if(ByteGreaterThan(baseDigit, b)) break;

}

baseDigit = ByteDivision(baseDigit, baseNumber);

 

int count;

 

while(!ByteEqual(baseDigit, 1)){

count = 0;

while(ByteGreaterThan(b, baseDigit)) {

b = ByteSubstract(b, baseDigit);

count++;

}

baseStr += map[count];

baseDigit = ByteDivision(baseDigit, baseNumber);

}

 

count = 0;

while(ByteGreaterThan(b, baseDigit)) {

b = ByteSubstract(b, baseDigit);

count++;

}

baseStr += map[count];

 

 

return baseStr;

}[/CSharp]

 

Ah, oh well the '[' issue in the CSharp tag is still around.

[JumpyNET]

Is there a simple way to do this?

 

Will this do?

 

   Private Sub TestConversion()
       Dim ByteArray() As Byte = {14, 215, 153}
       Dim Converter As New Converter(Of Byte, String)(AddressOf ConvertToBase32)
       Dim StringArray() As String = Array.ConvertAll(ByteArray, Converter)
       For i As Integer = 0 To ByteArray.Length - 1
           Debug.Print(ByteArray(i) & " --> " & StringArray(i))
       Next
   End Sub

   Public Shared Function ConvertToBase32(ByVal ByteValue As Byte) As String
       'Code from: http://en.wikipedia.org/wiki/Base_36#C.23_Conversion_Class
       Dim returnValue As String = ""
       Dim base36Chars = New Char() {"0"c, "1"c, "2"c, "3"c, "4"c, "5"c, _
                                     "6"c, "7"c, "8"c, "9"c, "a"c, "b"c, _
                                     "c"c, "d"c, "e"c, "f"c, "g"c, "h"c, _
                                     "i"c, "j"c, "k"c, "l"c, "m"c, "n"c, _
                                     "o"c, "p"c, "q"c, "r"c, "s"c, "t"c, _
                                     "u"c, "v"c, "w"c, "x"c, "y"c, "z"c}
       While ByteValue <> 0
           returnValue = base36Chars(ByteValue Mod base36Chars.Length) + returnValue
           ByteValue /= base36Chars.Length
       End While
       Return returnValue.ToUpper()
   End Function

[Arokh]

Since it converts every byte by itself to the base of 36, it is not what I need.

 

Lets assume I have a byte array of {1, 0},

now the number I need to convert is not 00000001 & 00000000 but

0000000100000000 (In decimal 256)

 

Your code would produce {"1", "0"} what I need is "74"

 

A quick site to test for lower numbers:

http://www.mste.uiuc.edu/users/exner/ncsa/base/default.html

 

But thanks for the nice wiki find,

based on that I can simplify my code a bit.

[PlausiblyDamp]

Just to check - are you wanting to treat the data as 16 bit values rather than 8 bit values?

[Arokh]

Just to check - are you wanting to treat the data as 16 bit values rather than 8 bit values?

 

Yes, that is exactly what I want,

only I'll use that function for >=192bit values.