>>>>Hi All, just messing around - not a work thing - if I have a string of binary digits such as
>>>>
>>>>

>>>>string s = "0101000001000101010101000100010101010010"
>>>>

>>>>
>>>>how do I convert it to text ?, all the Convert.* methods I've looked at require a byte[] array as an arg and I don't know how to create one !
>>>
>>>Pete,
>>>
>>>I'm not sure whether it's the best way to go , and I have not tested it either, but
>>>
>>>(1) initialize a BitArray
>>>(2) loop throught the string and assign the elements of the bitArray depending on 0 or 1
>>>(3) initialize a Byte array
>>>(4) I see that the BitARray has a CopyTo method wich accepts a Byte array
>>>http://msdn.microsoft.com/en-us/library/system.collections.bitarray.copyto.aspx
>>>
>>>
>>>Alternatively, you can directly create a byte array and loop through the string
>>>
>>>

>>>if( string[stringindex] == '1' ) {
>>>	the byte index = stringIndex / 8
>>>	the bit to set =  7 - (stringIndex %8),
>>>
>>>	// you may have to cast the right hand side to (byte)
>>>
>>>	byteArray[ stringIndex / 8] |= ( 1 <<  (  7 - (stringIndex %8)))
>>>
>>>	or maybe due to widening
>>>	byteArray[ stringIndex / 8]  = (byte)( byteArray[ stringIndex / 8]  | byteArray[ stringIndex / 8] | ( 1 <<  (  7 - (stringIndex %8))))
>>>}
>>>

>>
>>Hi Greg, thanks for your time - if you see my reply to Neil I can create the byte array but the ConvertToBase64String method returns rubbish. I read the M$ article and can't really see the point of BitArrays ? - maybe that's me :-(
>
>
>(1) BitArray - was my first thought - not the best way
>(2) ConvertToBase64String: I thought it was a binary string - base 64 encoding is something else
>
>(3) I see Viv has come up with a faster way

Just to exercise my new found 'Effective C#' knowledge :-} :

static IEnumerable<char> GetChars(string s)
   {
        return Enumerable.Range(0, s.Length / 8).Select(i =>
        Convert.ToChar(Convert.ToInt32(s.Substring(i * 8, 8),2)));
    }

then

string result = string.Empty;
foreach (char c in GetChars(s1))
{
     result += c;
 }

Nothing like making it complicated when simple would do :-}