CODEWITHSUNDEEP
c++
Jake Freelander
Jake Freelander

Reputation: 1471

Do i have to delete wchar_t that i allocated with new?

Lets say i have a class like this:

class LolClass {
    LPWSTR* stuff;
    LolClass::LolClass(LPWCHAR lols) {
        stuff = new LPWSTR[100];
        for (int i = 0; i < 100; i++) {
            stuff[i] = new wchar_t[wcslen(lols)+1];
            wcsncpy(stuffs[i], lols, wcslen(lols)+1);
        }
    }
    LolClass::~LolClass() {
        delete[] stuff;
    }
}

so if i call 

LolClass* veryfunny = new LolClass(L"lol!");

it would make me 100 lol's, problem is when i call 

delete veryfunny;

it deletes the pointer array but not the individual wchar_t's, if i try and loop through the wchar_t's and delete them then i just crash and i dont know what to do since i know for fact that they are still there even after i delete veryfunny (i checked by passing one of the pointers outside the class)

Thanks!

Upvotes: 1

Views: 3983

Answers (2)

Jake Freelander
Jake Freelander

Reputation: 1471

David Schwartz wins after all, the wchar's didnt let themselves be deleted because they werent null terminated

Upvotes: -1

Kerrek SB
Kerrek SB

Reputation: 477454

If you call

LolClass* veryfunny = new LolClass(L"lol!");

then you will eventually need to call:

delete veryfunny;

But for arrays, you need delete[]: stuff[i] = new wchar_t[n]; delete [] stuff[i];

In your code, you need to first loop over stuff and delete[] the elements, and then delete[] the array stuff itself.

Or just use a std::vector<std::wstring>.

Update: From what I understand, you're not actually worried about deleting *veryfunny, but rather about how to write a correct destructor for LolClass. Note that the destructor also gets invoked for global and automatic objects, e.g. { LolClass x(L"hello"); } /* boom */, so it doesn't really matter how you instantiate an object for LolClass. You have to get the class right in any case.

Upvotes: 6

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