在Windows批量中減去月份

Question

我想要運行並顯示上個月。當我嘗試減去月份時，它會使月份的最後一天不出現。

@echo off 

set FirstDay=01 

set Month=%date:~4,2% 

set Year=%date:~10,4% 



if %Month%==01 set LastDay=31 & goto foundate 
if %Month%==02 set LastDay=28 & goto foundate 
if %Month%==03 set LastDay=31 & goto foundate 
if %Month%==04 set LastDay=30 & goto foundate 
if %Month%==05 set LastDay=31 & goto foundate 
if %Month%==06 set LastDay=30 & goto foundate 
if %Month%==07 set LastDay=31 & goto foundate 
if %Month%==08 set LastDay=31 & goto foundate 
if %Month%==09 set LastDay=30 & goto foundate 
if %Month%==10 set LastDay=31 & goto foundate 
if %Month%==11 set LastDay=30 & goto foundate 
if %Month%==12 set LastDay=31 & goto foundate 



:foundate 
echo The year is: %Year% 
echo The month is: %Month% 
echo First day of this month is: %FirstDay% 
echo Last day of this month is: %LastDay% 

Answer 1

這裏有一段代碼，將讓比上月：

@echo off 

for /f "" %%# in ('WMIC Path Win32_LocalTime Get month /format:value') do (
    for /f %%Z in ("%%#") do set /a %%Z-1 
) 
if %month% equ 0 set month=12 
echo %month% 

更好地使用WMIC獲取日期部分，因爲它是獨立於不像%date%變量機器的日期格式。

編輯（如在意見中的要求）：

@echo off 


setlocal disableDelayedExpansion 
for /f "" %%# in ('"WMIC Path Win32_LocalTime Get month,year /format:value"') do (
    for /f %%Z in ("%%#") do set "%%Z" 
) 
set /a month=month-1 
if %month% equ 0 set month=12 
rem echo %month% -- %year% 
set /A "leap=!(year&3) + (!!(year%%100)-!!(year&15))" 
if %leap% equ 0 (set "m2=29") else (set "m2=28") 

setlocal enableDelayedExpansion 
set m1=31 
set m3=31 
set m4=30 
set m5=31 
set m6=30 
set m7=31 
set m8=31 
set m9=30 
set m10=31 
set m11=30 
set m12=31 

set premonLastDay=!m%month%! 




endlocal & set premonLastDay=%premonLastDay% 
if %month% equ 12 (

     set /a year=year-1 

) 

echo %premonLastDay%-%month%-%year% 

endlocal 

Answer 2

我由具有這些功能的函數庫。用這個圖書館做你想做的事情很簡單，請查看下面的內容。

這些函數位於代碼的末尾。只需複製到文件的末尾（在goto：eof之後）並使用指定的參數調用它們即可。

裏面給出的代碼：main應該做你所要求的。

備註：

• 已內置閏年檢查，因此，如果該年是閏年，Februrary將返回29天。
• 當複印功能可以將您的文件，請保留作者信息

代碼：

@echo off 
:main 
    :: Recommended to use GetDateIntl function, to get region-independent results (Check functions at the end of this file) 
    call :GetDateIntl Year Month Day /A 
    echo/Using GetDateIntl to get current date: %Year%-%Month%-%day% 
    echo/ 

    :: Call function to get last day of this month (Check functions at the end of this file) 
    call :GetLastDayOfMonth %Month% %Year% LastDay 
    echo This month is: %Month%/%Year% 
    echo First day of any month is always 1 
    echo Last day of this month is: %LastDay% 
    echo/ 

    :: Get previous month number 
    set /A "PMonth= %Month% - 1" 
    set "PYear=%Year%" 
    :: Correct PMonth and PYear if this month is December 
    if %PMonth%==0 (set "PMonth=12" & set /A "PYear= %PYear% - 1") 

    :: Call function to get last day of previous month (Check function after :main) 
    call :GetLastDayOfMonth %PMonth% %PYear% PLastDay 
    echo Previous month is: %PMonth%/%PYear% 
    echo Last day of previous month is: %PLastDay% 

goto:eof 


::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 
:GetDateIntl yy mm dd [/A] 
:: Returns the current date on any machine with regional-independent settings 
:: Arguments: 
:: yy = variable name for the year output 
:: mm = variable name for the month output 
:: dd = variable name for the day output 
:: /A = OPTIONAL, removes leading 0 on days/months smaller than 10 
:: 
:: By Cyberponk, v1.1 - 11/05/2016 
::   v1.0 - 2015 
:: 
SETLOCAL ENABLEEXTENSIONS 
if "%date%A" LSS "A" (set toks=1-3) else (set toks=2-4) 
for /f "tokens=2-4 delims=(-)" %%a in ('echo:^|date') do (
    for /f "tokens=%toks% delims=.-/ " %%i in ('date/t') do (
    set '%%a'=%%i 
    set '%%b'=%%j 
    set '%%c'=%%k 
) 
) 
if "%'yy'%"=="" set 'yy'=%'aa'% 
if %'yy'% LSS 100 set 'yy'=20%'yy'% 
endlocal&set %1=%'yy'%&set %4 %2=%'mm'%&set %4 %3=%'dd'%&goto :EOF 
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 


::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 
:IsLeapYear %year% IsLeap 
:: Checks if a year is a Leap Year (year that has 366 days) 
:: Arguments: 
:: %year% = year number input. Can be a number or a variable containing a 4 digit number 
:: IsLeap = result output containing 1 or 0 (1= is leap year, 0= not yeap lear) 
:: 
:: By Cyberponk, v1.1 - 11/05/2016 
:: 
SETLOCAL ENABLEEXTENSIONS 
    set /A "IsLeap=(!(%1 %% 4) & !!(%1 %% 100)) | !(%1 %% 400)" 
endlocal & set %2=%IsLeap%& goto:EOF 
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 


::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 
:GetLastDayOfMonth %month% %year% LastDay 
:: Gets the last day of a given month from a given year 
:: Arguments: 
:: %month% = month number input. Can be a number or a variable containing a number 
:: %year% = year for reference (used to check for leap years) 
:: LastDay = result output containing last day of the specified month 
:: 
:: By Cyberponk, v1.0 - 11/05/2016 
:: 
SETLOCAL ENABLEEXTENSIONS 
    :: Mathematical formula to last day of month 
    set /A "LastDay= 28 + (%1 + (%1/8)) %% 2 + 2 %% %1 + 2 * (1/%1) 

    :: Add 1 day if year is a Leap Year and month is February 
    call :IsLeapYear %2 IsLeap 
    if %LastDay%==28 set /A LastDay=%LastDay% + %IsLeap% 
endlocal & set %3=%LastDay%& goto:EOF 
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 

Answer 3

日期是併發工作，容易出錯，如果你能避免滾動您擁有，這樣做。

CMD不附帶本機日期庫，但.NET System.DateTime庫可通過PowerShell使用。以下PS腳本顯示瞭如何使用.NET來完成你所要求的功能。

GET-LastMonthStats.ps1

$lastmonth = (Get-Date).addMonths(-1) 

"The year is $($lastmonth.year)" 
"The month is $($lastmonth.Month)" 
"First day of this month is 01" 
"Last day of this month is $([DateTime]::DaysInMonth($lastmonth.year, $lastmonth.month))" 

幾乎所有這些腳本是格式化輸出。若要從CMD運行，用命令來啓動該

powershell.exe -ex bypass -f Get-LastMonthStats.ps1 

或者，你可以把整個劇本上一個（很長的）命令行，如果你不想創建一個單獨的文件.ps1。

powershell -c "$lastmonth = (Get-Date).addMonths(-1); 'The year is ' + $lastmonth.year; 'The month is ' + $lastmonth.Month; 'First day of this month is 01'; 'Last day of this month is ' + [DateTime]::DaysInMonth($lastmonth.year, $lastmonth.month)"