@echo off

if "%b2eprogramfilename%"==""  (
	echo To see any results you need to convert this file into an exe
	pause
	goto :eof
)

%extd% /inputbox "Strlen" "Enter a string to calculate its length" ""
if "%result%"=="" (exit) else (set string="%result%")
%extd% /strlen %string%
%extd% /messagebox Result "%result%"