Re: Initializing array of pointers to an object in a class constructor
John ha scritto:
I need an dynamic array of pointers to MyObj in a class.
Am I doing this right?
class SomeClass
{
public: SomeClass();
~SomeClass();
MyObj **pMyObj; // pointer to pointer == pointer to array of
pointers
int iNumPointers; // counter
}
class SomeClass
{
public:
SomeClass(int count);
private:
std::vector<std::vector<MyObj> > vec;
};
Or, if you really need pointers to MyObj (for example if MyObj is a
polymorphic base class):
class SomeClass
{
public:
SomeClass(int count);
private:
std::vector<std::shared_ptr<MyObj> > vec;
};
SomeClass::SomeClass()
{
iNumPointers = 123;
pMyObj = new MyObj*[iNumPointers]; // create array of iNumPointers
pointers to MyObj
for (int i = 0; i < iNumPointers; i++) pMyObj[i] = new MyObj(); // init each
pointer object
}
If MyObj is not polymorphic:
SomeClass::SomeClass(int count) :
vec(count)
{
}
If it is polymorphic:
SomeClass::SomeClass(int count) :
vec(count, std::shared_ptr<MyObj>(new MyObjDerived))
{
}
SomeClass::~SomeClass()
No destructor needed at all.
(If your compiler does not yet support shared_ptr, just use the version
from the Boost libraries.)
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