@echo off
FOR /F "usebackq delims==" %%i IN (`dir /s /ad /b`) DO @move "%%i"\*.* .\ && set /a js+=1
echo 共移动了%js%个文件
set /a js=0
pause

脚本

@echo off 
rem 计算指定天数之前的日期
set DaysAgo=1
rem 假设系统日期的格式为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 /a y_day = %DstYear%%DstMonth%%DstDay%
set /a day = %date:~0,4%%date:~5,2%%date:~8,2% 
rem 输出指定天数之前的日期
echo %y_day%
rem 输出当天日期
echo %day%
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