batch - attach variable to items on a list - batch-file

Question

Using the following code I am able to create a list of folders in a directory -
Setlocal EnableDelayedExpansion
set /p pattern=Enter Search Term:
echo.
dir /b /A:D %pattern%*
For example, if the user inputs con, the result may be
-construction1
-construction2
-construction_Docs
etc.
I would like to be able to attach a value to each item eg.
1_Construction1
2_Construction_Docs
etc.
Am I correcting in thinking that I would have to output the initial list I created to a .txt and then read and attach a variable to every line?
The end result would be a user being able to select one of the items based on the number we attach to it, and then have further actions being taken on that item.

Answer 1

dir /b /A:D %pattern%*|find /n /v ""
would yield
[1]construction1
[2]construction2
[3]construction_Docs
or
dir /b /A:D %pattern%*|findstr /n /v ":"
would yield
1:construction1
2:construction2
3:construction_Docs
You could then try
set /a max=0
for /f "delims=:" %%a in ('dir /b /A:D %pattern%*^|findstr /n /v ":" 2^>nul') do set /a max=%%a
which would set max to 0 if none found or the maximum number
The ^ tells batch that the pipe/> is part of the command to be executed
2>nul suppresses error messages in the case of no matches found
It's then a simple matter of
if %max%==0 echo none found&goto askagain
set /p "selection=Please choose [1..%max%] ? "
for /f "tokens=1*delims=:" %%a in ('dir /b /A:D "%pattern%*"^|findstr /n /v ":" 2^>nul') do if "%%a"=="%selection%" set "dirselected=%%b"&goto found
echo %selection% is invalid
goto askagain
:found
echo %dirselected% selected.
to make a complete job.

Answer 2

This task is relatively simple to achieve if you use the right tools, like an array:
#echo off
setlocal EnableDelayedExpansion
set /P "pattern=Enter Search Term: "
echo/
rem Get the folders, store they in the array and show the menu
set "num=0"
for /D %%f in (%pattern%*) do (
set /A num+=1
set "folder[!num!]=%%f"
echo !num!- %%f
)
if %num% equ 0 echo No folders found & goto :EOF
echo/
:selectFolder
set /P "num=Enter the desired folder: "
echo/
if not defined folder[%num%] goto selectFolder
set "item=!folder[%num%]!"
echo Folder selected: %item%
For further details on array management in Batch files, see this post.