copy array of classes or explicity call constructor

I have a dynamic array of classes (Buffer to be exact). When this array is full, I want to extend it. Unfortunately, since C++ has no equivalent to realloc() that works on classes, I have to allocate a new[] array and then copy everything and then delete[] the old array. Being not well trained in the ways of C++, I'm clueless on how to copy an array of classes. Does it work like copying an array of structs in C? The other way I could think of doing this is somehow explicitly calling the copy constructor of each new element.

A for loop, and per array element assignment.

> Does it work like copying an array of structs in C?
Yes.

So I can just use memcpy?

No, use the proper class assignment operator, if you have one.

for ( i = 0 ; i < howmany ; i++ ) newarr[ i ] = oldarr [ i ];

You might use a STL container for the job. Then you'll just have to worry about copy constructors / assignment operators if your class requires them.

Yes, the standard C++ vector class does all the "realloc" stuff for you. Beyond a learning exercise or some very specific coding requirements, you should really be using that over a dynamic array.