how to create a drop-down list allowing both multiple selections AND semi-automatic input.

Question

Hi everyone!

As this is my 1st post, I thank you for taking it into account, especially if the answer has already been published.

Here is my goal:
Starting from a long list of countries (l_country), I want to allow semi-automatic input (returns values from a drop-down list starting with the first letters written) while allowing the selection of several values (which will follow each other by a ",").

At the moment, I'm inspired by a VBA code that allows me the multiple selection (and that works very well).
On the other hand, for a single choice drop-down list only, I know how to use the functions OFFSET, MATCH, COUNTA, COUNTIF which allow me the semi-automatic input (using Data validation)..

My question is : how to combine these two queries ? in order to be able to make multi selection using semi automatic data entry. I exclude the possibility of User forms (the list of countries is much too long to check).

I hope to find on this forum some people who may already have the answer, or at least the knowledge to bring a solution.
(I can forward my VBA script if necessary).

Thanks in advance to all of you.

David.