Batch file read from largest registry sub-key? - scripting

Question

I am trying to modify my batch script to get the install path for a piece of software, however it needs to be version independent and the install path is stored in a version sub-key, so basically what I am looking to do is detect the greatest version sub-key and get the install path from there.
Here is what the code for getting the registry value looks like now:
FOR /F "skip=2 tokens=2,*" %%A IN ('REG.exe query "HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node......\6.30" /v "InstallLocation"') DO set "InstallPath=%%B"
Basically I want to not be dependent on the "6.30" part on the end of the key address, how can I do this?

Answer 1

Since I do not know which exact software you are looking at, I will reference Adobe Reader on Winodws 7 x64.
Answer:
The following example will output all of the sub keys within the parent.
for /f "delims=" %%A in ('reg query "HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Adobe\Acrobat Reader"') do if not "%%~A"=="" echo.%%~nxA
Output:
9.5
10.0
11.0
Sample:
From there it would just be a matter of remembering the largest and using it in the next query for the value data.
#echo off
setlocal EnableDelayedExpansion
set "xVersion="
set "xPath="
:: Retrieve Greatest Version
for /f "delims=" %%A in ('reg query "HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Adobe\Acrobat Reader"') do (
if not "%%~A"=="" if "%%~nxA" GTR "!xVersion!" set "xVersion=%%~nxA"
)
:: Validate Version
if "%xVersion%"=="" goto :eof
:: Retrieve Install Path
for /f "tokens=1,2,*" %%A in ('reg query "HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Adobe\Acrobat Reader\%xVersion%\Installer" /v Path') do (
set "xPath=%%~C"
)
:: Show Results
echo.%xPath%
endlocal
Output:
C:\Program Files (x86)\Adobe\Reader 10.0\
Bonus:
If you want to validate that the %%~nxA is a number, here is a batch routine of mine.
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:IsNumber <xReturn> <xInput> [xDelims]
:: Return true if the input is a base 10 number, else return false.
:::: Does not allow any seperators unless specified by xDelims. ,.[tab][space]
setlocal
if not "%~2"=="" set "xResult=true"
for /f "tokens=1 delims=1234567890%~3" %%n in ("%~2") do set xResult=false
endlocal & if not "%~1"=="" set "%~1=%xResult%"
goto :eof
:: Usage Example.
:: The variable xResult will be set to true if %%~nxA is a decimal number.
call :IsNumber xResult "%%~nxA" "."