【bat】文字列長の取得

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終わったら二倍・帳尻合わせ

@echo off
call :GET_LENGTH 123456789
echo %length%
goto :end

:GET_LENGTH
setlocal enabledelayedexpansion
	set n=0
	if "%~1" == "" goto :GET_LENGTH_END
	set str=%~1

	:GET_LENGTH_LOOP
	set /a n += 1
	if not "!str:~%n%,-%n%!" == "" goto :GET_LENGTH_LOOP

	set /a n = %n% * 2 - 1
	if not "!str:~%n%!" == "" set /a n += 1

	:GET_LENGTH_END
	rem echo %n%	%~1
endlocal & set length=%n%
exit /b

:end 
pause