BAT批處理 獲取當前系統日期前一天的日期
@echo off
rem 計算指定天數之前的日期
set DaysAgo=1
rem 假設系統日期的格式為yyyy-mm-dd
call :DateToDays %date:~0,4% %date:~5,2% %date:~8,2% PassDays
set /a PassDays-=%DaysAgo%
call :DaysToDate %PassDays% DstYear DstMonth DstDay
set DstDate=%DstYear%-%DstMonth%-%DstDay%
echo %DaysAgo%天的日期是%DstDate%
pause
goto :eof
:DateToDays %yy% %mm% %dd% days
setlocal ENABLEEXTENSIONS
set yy=%1&set mm=%2&set dd=%3
if 1%yy% LSS 200 if 1%yy% LSS 170 (set yy=20%yy%) else (set yy=19%yy%)
set /a dd=100%dd%%%100,mm=100%mm%%%100
set /a z=14-mm,z/=12,y=yy+4800-z,m=mm+12*z-3,j=153*m+2
set /a j=j/5+dd+y*365+y/4-y/100+y/400-2472633
endlocal&set %4=%j%&goto :EOF
:DaysToDate %days% yy mm dd
setlocal ENABLEEXTENSIONS
set /a a=%1+2472632,b=4*a+3,b/=146097,c=-b*146097,c/=4,c+=a
set /a d=4*c+3,d/=1461,e=-1461*d,e/=4,e+=c,m=5*e+2,m/=153,dd=153*m+2,dd/=5
set /a dd=-dd+e+1,mm=-m/10,mm*=12,mm+=m+3,yy=b*100+d-4800+m/10
(if %mm% LSS 10 set mm=0%mm%)&(if %dd% LSS 10 set dd=0%dd%)
endlocal&set %2=%yy%&set %3=%mm%&set %4=%dd%&goto :EOF
下面的程式碼測試報錯，日變成0開頭就不能減1了，就報錯
@echo off&setlocal enabledelayedexpansion
echo %date%
rem set yyyy=%date:~0,4%
rem set mm=%date:~5,2%
set dd=%date:~8,2%
set /a od=!dd!-1
rem if !od!==0 call :dd0
rem if !mm!==0 call :mm0
set yyyymmdd=!yyyy!年!mm!月!od!日
echo 昨天是：!yyyymmdd!
pause
:dd0
set /a mm=!mm!-1
for %%a in (1 3 5 7 8 10 12)do set %%add=31
set /a pddd=!yyyy!*10/4
set pd2d=!pddd:~-1,1!
set 2dd=28
if !pd2d!==0 set 2dd=29
for %%b in (4 6 9 11)do set %%bdd=30
set od=!%mm%dd!
goto :eof
:mm0
set /a yyyy=!yyyy!-1
set mm=12 && set od=31
goto :eof