China DOS Union

Due to work needs, there are a large number of computers that need to manually delete specified files 100 days after they are generated. There are always some machines that forget to delete them. Can any expert give some advice? Files are timed to be deleted, but they should not be regarded as viruses by the antivirus software.

The key to the problem is to judge what the date was 100 days ago today. It is related to the judgment of carrying over and removing zeros for the units and tens digits like 28, 29, 30, 31, and for the hundreds digit like 12 carrying over and removing zeros. I feel that this key point cannot be easily realized with batch processing.

There is also the judgment of common years and leap years. Although the idea is simple, the code will be very cumbersome.

A more direct way is:

Run it every three months!

schtasks /create /tn "My App" /tr "Full path of the program you want to execute" /sc monthly /mo 3

2, 3 floors

Look at the code

@echo off setlocal enabledelayedexpansion set dy=%date:~0,4% set dm=%date:~5,2% set dd=%date:~8,2% echo %dy%-%dm%-%dd% echo Calculate the date after 100 days. echo. pause>nul rem First check if the date dd is in the following conditions (3-12), consider January and February specially! rem Also, the default is that the year dy is a common year, and finally consider leap years. rem So you can just add one to dd in the end! for %%i in (3,5,7,8,10,12) do ( rem Check Odd Month (single month). if "%dm%" equ "%%i" ( set /a dm+=3 set /a dd+=8 rem At this time, dm has become a double month. goto :checkdd ) ) rem Check Even Month (double month). for %%j in (4,6,9,11) do ( if "%dm%" equ "%%j" ( set /a dm+=3 set /a dd+=9 rem At this time, dm has become a single month. goto :checkdd ) ) echo. echo %dm% pause :jan-feb rem Consider the situation of January and February. if "%dm%" equ "1" ( set /a dm+=3 set /a dd+=10 goto :chckdd ) if "%dm%" equ "2" ( set /a dm+=3 set /a dd+=10 goto :chckdd ) :checkdd rem At this time, dm has become a double month. rem Check if the date is greater than 30. if "%dd%" gtr "30" ( rem For example, June 24th should be changed to July 2nd set dm%+=1 & set /a ddd=!dd!%-30 ) rem At this time, dm has become a single month. rem Check if the date is greater than 31. if "%dd%" gtr "31" ( rem For example, July 24th should be changed to August 2nd. set dm%+=1 set /a ddd=!dd!%-31 ) :checkYear rem Check common year or leap year, as long as it is not a common year "... neq 0", add one to dd. set /a rmn=dy%\4 if "%rmn%" neq "0" (set /a dd+=1) ::Output the Result. echo The day in 100 is: %dy%-%dm%-%dd% schtasks /create /tn "DeleteTask" /m %dm% /tr "Full path of the program" pause>nul

Can't see the result, please help correct it.
Thank you!

The calculation method for leap years is incorrect. The correct algorithm is: A year that is divisible by 4 but not by 400 is not a leap year. For example, the year 2000 is a leap year, but the year 1900 is not a leap year;

The writing of `set dm%+=1` is incorrect. There is no such variable reference method, and when doing arithmetic operations, the switch `/a` should be added;

In addition, there is no need to handle January and February together. It is more reasonable to handle them together with large months like March, May, etc.

Moderator namejm's collection!
:: DateDel2.bat - Delete files modified before a specified number of days in the specified path :: Will Sort - 2005-9-2 - CMD@WinXP :: Notes: Parameter %1 specifies the number of days, where yesterday is 1, the day before yesterday is 2, and so on :: Parameter %1 specifies the file path, and if omitted, the current path will be processed :: Core algorithm: Ritchie Lawrence, updated 2002-08-13. Version 1.1 :: @echo off & setlocal ENABLEEXTENSIONS call :Date2Day %date:~0,10% sdays set /a sdays-=%1 call :Day2Date %sdays% difdate echo The following files modified before %difdate% in %cd% will be deleted: for /r %2 %%f in (*.*) do if "%%~tf" LEQ "%difdate%" echo "%%f" goto :EOF :Date2Day setlocal ENABLEEXTENSIONS for /f "tokens=1-3 delims=/-, " %%a in ('echo/%1') do ( set yy=%%a & set mm=%%b & set dd=%%c ) 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 %2=%j%&goto :EOF :Day2Date setlocal ENABLEEXTENSIONS set /a i=%1,a=i+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%-%mm%-%dd%&goto :EOF
Later, I searched and found that this code is from willsort!! Haha, the second line of the original code clearly states it's from willsort!!
Here are two linkshttp://www.cn-dos.net/forum/viewthread.php?tid=23926&fpage=1&highlight=%E7%BA%AF%E6%95%B0%E5%AD%97&page=1
http://www.cn-dos.net/forum/viewthread.php?tid=16676

[ Last edited by lotus516 on 2007-1-15 at 01:15 AM ]

!!!!!!!!!!!!!!!!!!!!Willsort is regarded as a god!!!!!!!!!!!!!!!!!!!!!

It makes me just want to cry....5555555555555555555555

[ Last edited by tghksj on 2007-1-14 at 12:11 PM ]

Originally posted by namejm at 2007-1-14 11:33:
The leap year calculation method is wrong. The correct algorithm is: A year that is divisible by 4 but not by 400 is not a leap year. For example, the year 2000 is a leap year, but the year 1900 is not a leap year;

　　set ...

The set... part was a carelessness, thank you

But the problem with January and February is like this

Suppose the current date is January, then from January to February, it changes by 31 days, and from February to March it changes by 28 days (in a common year);
Suppose the current date is March, then from March to April it is 31 days, okay, the program has no logical error;
But from April to May, it is 30 days, then, can you still use set... +=28?
So, you can't group January and March, May, July, August, October, December together!
By the same token, February and April, June, September, November can't be grouped together.

Therefore, only January and February are considered separately, not because grouping them together means they have any problem!
I don't know what everyone's opinion is?

First of all, I very much admire everyone's professional knowledge and enthusiasm for learning.

I, the younger brother, have something to say. DOS is not like C++, can it be simple? Don't make it seem very profound, it should be popular!

The landlord's statement is: After the file is generated, the specified file is automatically deleted after 100 days, right?

For example: To delete the temporary folder on drive C. Just create an xxx.bat file. The content is:
@echo off
del /f /s /q %systemdrive%\*.tmp
Then put this bat in the system's built-in scheduled tasks and set it to run every 100 days, and that's it...

Got it, very inspiring! Thank you everyone!

The idea on the 13th floor is very inspiring. Why make it too complicated when it can be simple?