How to get current datetime on Windows command line for using in a filename?

Lets say you want to have a .bat file that zips up a directory into an archive with the current date and time as part of the name, for example, Code_2008-10-14_2257.zip

In a windows console(CMD), the following command helps you get what you need

@echo off
For /f "tokens=2-4 delims=/ " %a in ('date /t') do (set mydate=%c-%a-%b)
For /f "tokens=1-2 delims=/:" %a in ('time /t') do (set mytime=%a-%b)
echo %mydate%_%mytime%
@echo on

echo "Testing 123" >> "testFile_%mydate%_%mytime%.txt"

This would output the filename appended with the desired time format.

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