Converting const char* to CString without Memory Leak

[nsyforce]

What is the correct way to convert a const char* to a CString? I'm
somewhat of a newbie and have tried several ways. While they all
convert ok, I'm using a profiler that shows a memory leak for every
option. Here's what I have tried:

const char* test;
test = getMyChar();
//CString myCString((LPCTSTR)test);
//CString myCString(test);
CString myCString = new CString(test);
delete myCString;

Thanks in advance for your help

 

[Howard]

What is the correct way to convert a const char* to a CString? I'm
somewhat of a newbie and have tried several ways. While they all
convert ok, I'm using a profiler that shows a memory leak for every
option. Here's what I have tried:

const char* test;
test = getMyChar();
//CString myCString((LPCTSTR)test);
//CString myCString(test);
CString myCString = new CString(test);
delete myCString;

Thanks in advance for your help

The CString class is, I believe, and MFC class, and not topical in this
newsgroup.

However, the problem most likely lies in the fact that you're making a call
to something called getMyChar(), which, I must assume (not seing its code),
allocates storage for the string. You probably need to recover THAT memory,
most likely by calling "delete [] test;". But not seeing the code for
getMyChar, I can't say for sure.

By the way, if that IS the way that getMyChar works, I see a couple problems
with it. First, its name implies that it gets a char, not a string. It
should say precisely what it does.

But more important, it's not the best practice to have allocation done
inside a function like that. It hides the fact that you need to do the
delete yourself.

A better method is to allocate the memory yourself, and pass the array (and
its length, to be safe) to a function which fills out the array for you.

Or, your function could work directly on a CString, instead of a char*
pointer.

Or, a better idea would be to use the RAII design. Look it up on Google for
more details.

Or, even better would be to use the std::string class instead of a char
array and CString.

-Howard

 

[Greg Schmidt]

Or, even better would be to use the std::string class instead of a char
array and CString.

In general, yes, but many MFC functions and classes take CString
parameters, and it's often easier to just work with CStrings than to
keep converting back and forth.

 

[nsyforce]

Thank you both for your input and good ideas.
It seems as though there wasn't really a problem after all. The values
were being stored in cache, and the profiler was pointing at that piece
of code because that's where it was initially created. (I believe this
is how the profiler was working). It doens't show a leak when the
strings are cleared out of cache.

(The example I gave was kind of a slimmed down version of what the code
was actually doing. Like Greg Schmidt mentioned, I was calling a
different class that was returning the const char*, and I couldn't
change that)