Re: How can I get the size of this?


"Carl" <carl8421@xxxxxxx> wrote in message
news:uA09JQwRFHA.3336@xxxxxxxxxxxxxxxxxxxxxxx

> I am now having a problem at using sizeof() function

Don't think of it as a function - it isn't one. It's an operator.
I perefer to use it without brackets just to remind myself that it
is an operator.

Operating on something declared as a pointer returns the size of
the pointer.

Operating on something declared as an array returns the size of the
array (and not the size of the pointer you would have by using the
array name as a pointer).

So you have to be very clear which you have.

So for example in

> int szData = sizeof( (char*) Data )/ sizeof( Data[0] );

you are explicitly finding the ratio of the size of a char *
(unambiguously, because you have explicitly cast it) and dividing by
the size of a char *.

In these matters "typedef" is often your friend!

LPCSTR is already typedef'd as "const char *", so use it.

> LPCSTR Data[]={"abc","bcd","cde","def","wot","shame"};

makes Data unambiguously an array of LPCSTRs, and

int nSize = sizeof Data;

should get you the answer 24 (six times sizeof LPCSTR).


Dave
--
David Webber
Author MOZART the music processor for Windows -
http://www.mozart.co.uk
For discussion/support see
http://www.mozart.co.uk/mzusers/mailinglist.htm


.

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