wshShell and WMIC working together in batch? - list

Question

I was trying to create a scrollable list for a batch file using the method found here: Scrollable Lists in .bat Files
Credit to https://stackoverflow.com/users/778560/aacini
One I tried adding back in my code for my regular batch a few lines at a time, I noticed that the solution doesn't work when I use WMIC. What is the reason for this and is there an easy solution? You can run the below code and then un-comment the WMIC line and see it will not work anymore.
Edit: I am using Windows 7
Thanks!
#if (#CodeSection == #Batch) #then
#echo off
setlocal EnableDelayedExpansion
color F0
::FOR /F "tokens=2 delims==" %%A IN ('WMIC csproduct GET Name /VALUE ^| FIND /I "Name="') DO SET machine=%%A
Echo Reset or Continue
Set MenuOptions=RESET Continue
call :ShowMenu
pause
exit
:ShowMenu
set numOpts=0
for %%a in (%MenuOptions%) do (
set /A numOpts+=1
set "option[!numOpts!]=%%a"
)
rem Clear previous doskey history
doskey /REINSTALL
rem Fill doskey history with menu options
cscript //nologo /E:JScript "%~F0" EnterOpts
for /L %%i in (1,1,%numOpts%) do set /P "var="
rem Send a F7 key to open the selection menu
cscript //nologo /E:JScript "%~F0"
set /P "MenuSelected=Option Selected: "
echo/
#end
var wshShell = WScript.CreateObject("WScript.Shell"),
envVar = wshShell.Environment("Process"),
numOpts = parseInt(envVar("numOpts"));
if ( WScript.Arguments.Length ) {
// Enter menu options
for ( var i=1; i <= numOpts; i++ ) {
wshShell.SendKeys(envVar("option["+i+"]")+"{ENTER}");
}
} else {
// Enter a F7 to open the menu
wshShell.SendKeys("{F7}");
}

Answer 1

SendKeys Method sends one or more keystrokes to the active window. Unfortunately, Sendkeys() sometimes fails usually due to focus or timing, both troublesome and difficult to solve problems. I tried pause and timeout, tried WshShell.AppActivate in various combinations, all without success…
Finally, I found culprit in clearing previous doskey history via doskey /REINSTALL command: it installs a new copy of doskey. I can recommend more intuitive (and less invasive) method to clear the doskey command history buffer:
doskey /ListSize=0
doskey /ListSize=50
Bonus: FOR loops explanation.
outer %%A loop to retrieve the name property;
inner %%a loop to remove the ending carriage return in the value returned: wmic behaviour: each output line ends with 0x0D0D0A (<CR><CR><LF>) instead of common 0x0D0A (<CR><LF>).
Credit: Dave Benham's WMIC and FOR /F: A fix for the trailing <CR> problem
Working script (Windows 8.1 64 bit):
#if (#CodeSection == #Batch) #then
#echo OFF
setlocal EnableDelayedExpansion
REM color F0
FOR /F "tokens=2 delims==" %%A IN ('
WMIC csproduct GET Name /VALUE ^| FIND /I "Name="
') DO FOR %%a in ("%%~A") DO SET "_machine=%%~a"
Echo Reset or Continue %_machine%
Set "MenuOptions=%_machine% RESET Continue" expanded merely for debugging purposes
call :ShowMenu
REM pause
exit /B
:ShowMenu
set numOpts=0
for %%a in (%MenuOptions%) do (
set /A numOpts+=1
set "option[!numOpts!]=%%a"
)
rem Clear previous doskey history
REM this causes problems: doskey /REINSTALL
doskey /ListSize=0
doskey /ListSize=50
rem Fill doskey history with menu options
cscript //nologo /E:JScript "%~F0" EnterOpts
for /L %%i in (1,1,%numOpts%) do set /P "var="
rem Send a F7 key to open the selection menu
cscript //nologo /E:JScript "%~F0"
set /P "MenuSelected=Option Selected: "
echo/
goto :eof
#end
var wshShell = WScript.CreateObject("WScript.Shell"),
envVar = wshShell.Environment("Process"),
numOpts = parseInt(envVar("numOpts"));
if ( WScript.Arguments.Length ) {
// Enter menu options
for ( var i=1; i <= numOpts; i++ ) {
wshShell.SendKeys(envVar("option["+i+"]")+"{ENTER}");
}
} else {
// Enter a F7 to open the menu
wshShell.SendKeys("{F7}");
}