Re: Cast CString to unsigned char*

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From: Nathan Holt (nathanh_at_ccei-nm.com)
Date: 08/06/04 

Date: Fri, 6 Aug 2004 09:20:16 -0600

"Dan Bloomquist" <EXTRApublic20@lakeweb.com> wrote in message
news:41113785.1060109@lakeweb.com...
>
>
> Frank E Rogers wrote:
> > Is there anyone who can tell me how to cast a CString to unsigned char*
?
>
> use two casts:
> (unsigned char*)(LPCTSTR)str;
>
> The LPCTSTR cast is necessary to invoke the overloaded operator of
> CString to return a pointer. Once you have that pointer, you can recast
it.
>
> Best, Dan.
>
> --
> http://lakeweb.net
> http://ReserveAnalyst.com
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    As for (unsigned char*)(LPCTSTR)str; I recommend NOT doing that. It may
be useful for calling functions in a library that isn't const correct, but
I'd tend to assume that such a library actually does change the characters
in the string. This is bad because the string buffer may be shared with
several other string objects, and a change to the string's characters will
change all of the strings that use the buffer.
    The proper way to get an "unsigned char *" is to use GetBuffer and call
ReleaseBuffer after you are done with it. You may have to cast the result
of GetBuffer from "char *" to "unsigned char *".

                                        Nathan Holt

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