There are quite a number of solutions out there.
It's not hard to do for dragging between a limited set of controls.
I did it just for fun several years ago and don't think I have the code
anymore.
The mouse knows where it is and I used a right mouse down to copy the
contents
Then you check to see if you are in an allowed field and paste the info in
when the button is released and cut (or not ) the old stuff.