Declare member variable on stack or heap

[_Flaviu]

How is more efficient to have, a CMap member variable created on the stack, or on the heap, even the values of CMap are just pointers:

CMap m_MapContactInfo;

or

CMap* m_pMapContactInfo;

knowing that this CMap could contain thousands of elements ...

[Lost User]

Probably best on the heap if it contains large amounts of data. You also need to consider scope, i.e. how long will the object need to remain in memory?

[_Flaviu]

"how long will the object need to remain in memory?" As long as object that contain m_pMapContactInfo are alive ... I mean:

CMyObject::CMyObject()
{
m_pMapContactInfo = new CMap;
}

and

CMyObject::~CMyObject()
{
if(NULL != m_pMapContactInfo)
delete m_pMapContactInfo;
}

[Lost User]

Flaviu2 wrote:

As long as object that contain m_pMapContactInfo are alive

Only you know how long that will be.

[Victor Nijegorodov]

CMap class creates its content data in the heap. It is by design. So you can create your CMap instance on the stack and not worry!

[_Flaviu]

"CMap class creates its content data in the heap. It is by design." This is a good news ! (I didn't read that by now) ... thank you.

[_Flaviu]

In fact, the m_pMapContactInfo are member variable into CView derived class ... so, as long the view are opened, the m_pMapContactInfo exist ... but what is matter how long the CMap object are exist ?

[Lost User]

It only matters in that you need to place the CMap object, and all its members, in the correct place to ensure it does not get destroyed at the wrong time. The fact that you posted this question suggests that you were not sure.

[Hometurph Indi]

i am still not having a perfect solution with both options Deep Cleaning Delhi Home Cleaning Delhi

[Victor Nijegorodov]

Hometurph Indi wrote:

i am still not having a perfect solution with both options

Define perfect.:cool: