Extract and expand a line from a list box to a text box and after the edit is complete contract it back to the list box from the textbox

Question

The rules I created for a name: A segment letter, a separator, a 4 character abbreviation, a separator, and a number counter 1 through 999.

1 LETTER, A THROUGH Z, '+', 1 THROUGH 4 LETTERS, ':', and 3 NUMBERS THAT AUTO-INCREMENT AS DATA IS COLLECTED

           From list box to textbox -->

    listbox                 textbox

A SINGLE POINT A+L:001 | A+L:001 1 LINE 2 POINTS A+LL:001-002 | A+LL:001,A+LL:002 A LINE 2 NAMES A+LLL:001-003,A+LLLL:001-002 | A+LLL:001,A+LLL:002,A+LLL:003,A+LLLL:001,A+LLLL:002

           <-- To list box from textbox

When the first point of the day B+BLDG:001 is collected the listbox would initialize

B+BLDG:001 --> list box string #1

I collect 3 more BLDG points

B+BLDG:001-004 --> list box string #1

I start a another line with SHED shots, I have already collected 11 SHED shots

B+BLDG:001-004 --> list box string #1 B+SHED:012 --> list box string #2

I collect 3 more SHED points

B+BLDG:001-004 --> list box string #1 B+SHED:012-015 --> list box string #2

for illustration purposes I want to insert a SHED shot after B+BLDG:002

I click on list box string #1, and the textbox is filled, it has EXPANDED

B+BLDG:001,B+BLDG:002,B+BLDG:003,B+BLDG:004 <-- in textbox

I insert B+SHED:012

B+BLDG:001,B+BLDG:002,B+SHED:012,B+BLDG:003,B+BLDG:004 <-- in textbox

After editing the texbox, the listbox is updated, and it has CONTRACTED

B+BLDG:001-002,B+SHED:012,B+BLDG:003-004 --> list box string #1 B+SHED:012-015 --> list box string #2

It's kind of like an expand and contract folder triangle button click, points instead of files.

I am coding in c++ visual studio NET framework

Thank you in advance !