Re: Working with bytes vs characters

["Paul Rehill" <paul.rehill@gmail.com>]

On Sun, Sep 28, 2008 at 3:25 PM, Paul Rehill <paul.rehill@gmail.com> wrote:
> I am trying to code to calculate the number of bytes rather than
> characters to read incoming data from sockets.
>
> I am aiming to read in data to the end of some closing tag, let's call
> it Str1="</sometag>" that has been extracted using the Lookahead
> function for a socket.  sLook is the full string data obtained using
> the LookAhead function.
>
> If I was only working with characters and not bytes, I could use the
> following code to determine iTagEnd which represents the number of
> characters to be read by a socket's read function:
>    iFoundTag=Instr(sLook, Str1)
>    iTagLength=Len(Str1)
>    iTagEnd=iFoundTag+iTagLength-1
>
> But since I am working with bytes, I have replaced Instr with InstrB,
> Len with LenB and 1 in the above code with LenB(Left(Str1,1)) as in
> the following code:
>
>    iFoundTag=InstrB(sLook, Str1)
>    iTagLength=LenB(Str1)
>    iTagEnd=iFoundTag+iTagLength-LenB(Left(Str1,1))

Looking at this again.  I think I should still be using
iTagEnd=iFoundTag+iTagLength-1 even when dealing with bytes as
iFoundTag returns the first byte as an integer (rather than 2 bytes
when each character may be represented by 2 bytes) and so I need to
subtract 1 to capture the correct number of bytes to be read up to and
including the end tag.

Is this right?

Thanks

Paul

_______________________________________________
Unsubscribe or switch delivery mode:
<http://www.realsoftware.com/support/listmanager/>

Search the archives:
<http://support.realsoftware.com/listarchives/lists.html>