C / C++ / MFC

CString* strData = new CString;<br />
<br />
if(NULL != strData)<br />
{<br />
 delete strData;<br />
}

Taruni wrote:

But what should be the condition to test whether strData is actually initialised

CString* strData = NULL; // always initialize pointers
int nCount;
if(nCount > 0)
{
strData = new CString[nCount];
}
...
if (strData)
{
  delate [] strData;
  strData = NULL; // always mark deleted pointers
}

Taruni wrote:

But I am trying to delete an array of pointers of CString type.

CString* strData = NULL;<br />
int nCount;<br />
if(nCount > 0)<br />
{<br />
strData = new CString[nCount];<br />
}<br />
<br />
.<br />
.<br />
.<br />
if(NULL != strData)<br />
{<br />
delete[] strData;<br />
}

Paresh Chitte wrote:

Initialise strData with NULL

Paresh Chitte wrote:

and check strData against NULL before deleting.

Nemanja Trifunovic wrote:

That's not necessary. Deleting NULL is guaranteed to be a no-op.

if (strData)
{
  delete [] strData;
  strData = NULL;
}

Paresh Chitte wrote:

if(NULL != strData)
{
delete[] strData;
}

if(NULL != strData)
{
  delete[] strData;
  strData = NULL;
}

Cedric Moonen wrote:

You should always always initialize your pointers to NULL.

<br />
CString* strData = new CString[count];<br />

<br />
vector<CString> strData;<br />

<br />
CStringArray strData;<br />

Nemanja Trifunovic wrote:

Unless you initialize them with something else

I.e., this is acceptable:


CString* strData = new CString[count];

Nemanja Trifunovic wrote:

In any case this new/delete construct is overused and leads to code that is not exception-safe and is hard to maintain. Wouldn't it be easier and safer to simply write something like:

CPallini wrote:

I don't blame for new/delete usage. You've to be disciplined though.

A* a = new A;
... // what if this trows?
B* b = new B;
... // what if this trows?
C* c = new C;
... // what if this trows?
delete c;
delete b;
delete a;