如果你不需要这个格式:

2009_07_28__08_36_01

然后你可以使用以下3行代码，使用%date%和%time%:

set mydate=%date:/=%
set mytime=%time::=%
set mytimestamp=%mydate: =_%_%mytime:.=_%

注意:字符/和:被删除，字符。空格被下划线取代。

示例输出(摄于8/5/15星期三下午12:49，时间为50秒93毫秒):

echo %mytimestamp%
Wed_08052015_124950_93

REM Assumes UK style date format for date environment variable (DD/MM/YYYY).
REM Assumes times before 10:00:00 (10am) displayed padded with a space instead of a zero.
REM If first character of time is a space (less than 1) then set DATETIME to:
REM YYYY-MM-DD-0h-mm-ss
REM Otherwise, set DATETIME to:
REM YYYY-MM-DD-HH-mm-ss
REM Year, month, day format provides better filename sorting (otherwise, days grouped
REM together when sorted alphabetically).

IF "%time:~0,1%" LSS "1" (
   SET DATETIME=%date:~6,4%-%date:~3,2%-%date:~0,2%-0%time:~1,1%-%time:~3,2%-%time:~6,2%
) ELSE (
   SET DATETIME=%date:~6,4%-%date:~3,2%-%date:~0,2%-%time:~0,2%-%time:~3,2%-%time:~6,2%
)

ECHO %DATETIME%

希望这能有所帮助:

set MM=%date:~4,2%
set DD=%date:~7,2%
set YYYY=%date:~10,4%

echo %DD%_%MM%_%YYYY%

这将打印05_06_2021

为了生成一个YYYY-MM-DD hh:mm:ss(24小时)时间戳，我使用:

SET CURRENTTIME=%TIME%
IF "%CURRENTTIME:~0,1%"==" " (SET CURRENTTIME=0%CURRENTTIME:~1%)
FOR /F "tokens=2-4 delims=/ " %%A IN ('DATE /T') DO (SET TIMESTAMP=%%C-%%A-%%B %CURRENTTIME%)

这个bat文件(保存为datetimestr.bat)生成3次datetime字符串:(1)长datetime字符串，包含星期几和秒， (2)短的datetime字符串没有它们和 (3)短版代码。

@echo off
REM "%date: =0%" replaces spaces with zeros
set d=%date: =0%
REM "set yyyy=%d:~-4%" pulls the last 4 characters
set yyyy=%d:~-4%
set mm=%d:~4,2%
set dd=%d:~7,2%
set dow=%d:~0,3%
set d=%yyyy%-%mm%-%dd%_%dow%

set t=%TIME: =0%
REM "%t::=%" removes semi-colons
REM Instead of above, you could use "%t::=-%" to 
REM replace semi-colons with hyphens (or any 
REM non-special character)
set t=%t::=%
set t=%t:.=%

set datetimestr=%d%_%t%
@echo  Long date time str = %datetimestr%

set d=%d:~0,10%
set t=%t:~0,4%
set datetimestr=%d%_%t%
@echo Short date time str = %datetimestr%


@REM Short version of the code above
set d=%date: =0%
set t=%TIME: =0%
set datetimestr=%d:~-4%-%d:~4,2%-%d:~7,2%_%d:~0,3%_%t:~0,2%%t:~3,2%%t:~6,2%%t:~9,2%
@echo Datetimestr = %datetimestr%

pause

为了给予适当的赞扬，我将彼得·莫滕森(Peter Mortensen)(14年6月18日21:02)和欧佩罗(opello)(8月25日至11日14:27)的概念融合在一起。

您可以写得更短，但是这个长版本使阅读和理解代码变得更容易。

也许是这样的:

@call:DateTime

@for %%? in (
    "Year   :Y"
    "Month  :M"
    "Day    :D"
    "Hour   :H"
    "Minutes:I"
    "Seconds:S"
) do @for /f "tokens=1-2 delims=:" %%# in (%%?) do @for /f "delims=" %%_ in ('echo %%_DT_%%$_%%') do @echo %%# : _DT_%%$_ : %%_

:: OUTPUT
:: Year    : _DT_Y_ : 2014
:: Month   : _DT_M_ : 12
:: Day     : _DT_D_ : 17
:: Hour    : _DT_H_ : 09
:: Minutes : _DT_I_ : 04
:: Seconds : _DT_S_ : 35

@pause>nul

@goto:eof

:DateTime
    @verify errorlevel 2>nul & @wmics Alias /? >nul 2>&1
    @if not errorlevel 1 (
        @for /f "skip=1 tokens=1-6" %%a in ('wmic path win32_localtime get day^,hour^,minute^,month^,second^,year /format:table') do @if not "%%f"=="" ( set "_DT_D_=%%a" & set "_DT_H_=%%b" & set "_DT_I_=%%c" & set "_DT_M_=%%d" & set "_DT_S_=%%e" & set "_DT_Y_=%%f" )
    ) else (
        @set "_DT_T_=1234567890 "
    )
    @if errorlevel 1 (
        @for %%? in ("iDate" "sDate" "iTime" "sTime" "F" "Y" "M" "D" "H" "I" "S") do @set "_DT_%%~?_=%%~?"
        @for %%? in ("Date" "Time") do @for /f "skip=2 tokens=1,3" %%a in ('reg query "HKCU\Control Panel\International" /v ?%%~? 2^>nul') do @for /f %%x in ('echo:%%_DT_%%a_%%') do @if "%%x"=="%%a" set "_DT_%%a_=%%b"
        @for /f "tokens=1-3 delims=%_DT_T_%" %%a in ("%time%") do @set "_DT_T_=%%a%%b%%c"
    )
    @if errorlevel 1 (
        @if "%_DT_iDate_%"=="0" (set "_DT_F_=_DT_D_ _DT_Y_ _DT_M_") else if "%_DT_iDate_%"=="1" (set "_DT_F_=_DT_D_ _DT_M_ _DT_Y_") else if "%_DT_iDate_%"=="2" (set "_DT_F_=_DT_Y_ _DT_M_ _DT_D_")
        @for /f "tokens=1-4* delims=%_DT_sDate_%" %%a in ('date/t') do @for /f "tokens=1-3" %%x in ('echo:%%_DT_F_%%') do @set "%%x=%%a" & set "%%y=%%b" & set "%%z=%%c"
        @for /f "tokens=1-3 delims=%_DT_T_%" %%a in ("%time%") do @set "_DT_H_=%%a" & set "_DT_I_=%%b" & set "_DT_S_=%%c"
        @for %%? in ("iDate" "sDate" "iTime" "sTime" "F" "T") do @set "_DT_%%~?_="
    )
    @for %%i in ("Y"                ) do @for /f %%j in ('echo:"%%_DT_%%~i_%%"') do @set /a _DT_%%~i_+=  0 & @for /f %%k in ('echo:"%%_DT_%%~i_:~-4%%"') do @set "_DT_%%~i_=%%~k"
    @for %%i in ("M" "D" "H" "I" "S") do @for /f %%j in ('echo:"%%_DT_%%~i_%%"') do @set /a _DT_%%~i_+=100 & @for /f %%k in ('echo:"%%_DT_%%~i_:~-2%%"') do @set "_DT_%%~i_=%%~k"
@exit/b