How to build a dynamic array in C++ and return it back to C#/.NET

Question

I have to find the way to build the array of structs on C++ Win32 side. I don\'t have the initial number of items. It should be very fast to resize that array.

When

Answer 1

Generally if your C++ dll compiled with CLI support you can simply use managed containers. If you don't want your dll to be compiled with CLI option, then you may write small C++/CLI wrapper dll which will call methods from native C++ dll and store objects in the managed container. Another possible solution is to change interface of the C++ lib to return objects by indexes, support insertion and/or removal.

std::vector vec;

void init() {
    //read data to vec
}

CFoo getIthElement(int i) {
    return vec[i];
}

int getElementCount() {
    return vec.size();
}

So you will use getIthElement and getElementCount functions on the C# side.