dateTime.bat

@echo off
setlocal

:: Define simple macros to support JavaScript within batch
set "beginJS=mshta "javascript:close(new ActiveXObject('Scripting.FileSystemObject').GetStandardStream(1).Write("
set "endJS=));""

 :: Direct instantiation requires that output is piped
 %beginJS% (new Date()).getTime() %endJS% | findstr "^"

:: FOR /F does not need pipe
for /f %%N in (
  '%beginJS%(new Date()).getTime()%endJS%'
) do set date_time=%%N
echo date_time=%date_time%

endlocal