Re: CArray vs CMap

David Wilkinson <>
Fri, 13 Jun 2008 07:50:51 -0400
Giovanni Dicanio wrote:

CMap and CArray are both valid tools, but for different tasks.

If the key is an integer represented by item position, then there is no
doubt in choosing CArray< Class >.

But if you want to access the items stored in a container using a different
kind of key, for example a string, then CMap is the tool to choose.
(Note that there are also STL containers, like std::vector, std::map, etc.
which seems to be more carefully designed than MFC containers, at the cost
of maybe a bit more hard learning curve. However, STL containers with their
"ecosystem" of iterators and algorithms are a very versatile and powerful
tool, if you can invest some time and intellectual energy to learn them.)


Even with an integer key, a map can be preferable if the desired key values are

As you know, I agree with you about using the STL containers rather than the MFC

But CMap can potentially be more efficient than std::map for large containers
because it is a hash-map. (Modern versions of the C++ standard library have
hash_map, but I have never used it).

David Wilkinson
Visual C++ MVP

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