China DOS Union

For example, 20060110
How to determine what day of the week it is based on the above date?

Here's an idea: First, determine a date for which you already know what day of the week it is. Then calculate the difference in days between 20060110 and that date. Then divide the difference by 7 and take the remainder - the key point is calculating the difference between the two dates, which is transformed back to the classic old topic: What day of the week was N days before a certain date?

I can calculate the date n days ago, but just can't calculate the day of the week.
For example, today is 20070205 Monday, the date n days ago is 20061210.
How to calculate it?
How to subtract 20061210 from 20070205?

The moderator's statement is quite right. First of all, you need to have a reference object. The rest is to convert the date interval into decimal days, subtract 7 minus the reference week, and then divide by 7 to find the remainder.

Another alternative day-of-the-week query: )

1. @ echo off && setlocal
   
2. :: Redtek.2006 bbs.cn-dos.net Query what day of the week a certain year/month/day is
   
3. 
   
4. 
   
5. 
   
6. set /p setDate=Please enter the date to query: (Format: year-month-day)
   
7. 
   
8. 
   
9. :: Backup current date and set new date
   
10. 
    
11. for /f %%i in ('date/t') do set "Current date backup=%%i"
    
12. echo %setDate%|date >nul
    
13. 
    
14. 
    
15. :: Display the queried date and restore the current date to the backup date
    
16. 
    
17. echo. && echo The detailed information of the date you want to query is: %date% ] && echo.
    
18. echo %Current date backup%|date >nul
    
19. 
    
20. 
    
21. 
    
22. 
    
23. Pause
    

Redtek@sweetmeet.comPosted on: 2007-02-05 20:26

Note: Do not use this code on computers such as servers that are closely connected to the date.

　　Because the implementation principle is to first back up the current date, then set the specified date, use the system %date% to get the day of the week, and then restore the date before the calculation.

　　If some date-sensitive programs are installed on the computer, such as: JCreator pro for Java development and other sensitive software, if the date is changed to the past, even if it is changed back, it has become invalid.

Brother upstairs, just one word, "Like"

Using the newly learned VBS
@echo off for %%n in (week1-日 week2-一 week3-二 week4-三 week5-四 week6-五 week7-六) do set Tmp$=%%n&&call set %%Tmp$:-==%% :loop cls echo. set input= set /p input= Please enter the date (format: 2007/1/1): if not defined input exit echo. >tmp.vbs echo wscript.echo weekday(#%input%#) for /f "tokens=* delims=-" %%i in ('"cscript //nologo tmp.vbs"') do call echo Week %%week%%i%% del tmp.vbs echo. pause goto loop

Add one modified according to floor 9:
@echo off for %%n in (week1-日 week2-一 week3-二 week4-三 week5-四 week6-五 week7-六) do set Tmp$=%%n&&call set %%Tmp$:-==%% :loop cls echo. set input= set /p input= Please enter the date (format: 20070101): if not defined input exit echo. >tmp.vbs echo wscript.echo Weekday(CDate("%input:~0,4%-%input:~4,2%-%input:~6,2%")) for /f "tokens=* delims=-" %%i in ('"cscript //nologo tmp.vbs"') do call echo Week %%week%%i%% del tmp.vbs echo. pause goto loop

[ Last edited by zh159 on 2007-2-6 at 03:07 PM ]

The method on the 5th floor is indeed good, but it seems a bit less perfect to change the system time. Do you all have any other good ideas?

Why not use VBS?
<script language="vbscript"> <!-- MsgBox Weekday(CDate("2006-01-10")-1) --> </script>

I remember there was a formula in the Olympiad in Mathematics when I was a child, and I can check it again.

The problem of getting the difference between two dates has been solved. Now the problem is how to determine the day of the week?
//For example, given Thursday, February 8, 2007, how to determine the day of the week 18 days ago?
That is, how to subtract 1 or 2 from the current day of the week...?

[ Last edited by 26933062 on 2007-2-8 at 03:47 AM ]

Give you a boost, it's getting more challenging

Originally posted by 26933062 at 2007-2-8 03:40:
The difference between two dates has been solved. Now the problem is how to determine the day of the week?
// For example, given 2007/02/08/Thursday, how to determine the day of the week 18 days ago?
That is, how to subtract 1 or 2 from the current day of the week..........?

...

@echo off for %%n in (week1-日 week2-一 week3-二 week4-三 week5-四 week6-五 week7-六) do set Tmp$=%%n&&call set %%Tmp$:-==%% :loop cls echo. set input= set week=+0 set /p input= Please enter the date (format: 20070101): if not defined input exit set /p week= Please enter the number of days interval (format: +8(-8), default is 0): echo. >tmp.vbs echo wscript.echo Weekday(CDate("%input:~0,4%-%input:~4,2%-%input:~6,2%")%week%) for /f "tokens=* delims=-" %%i in ('"cscript //nologo tmp.vbs"') do call echo Day of the week%%week%%i%% del tmp.vbs echo. pause goto loop

MsgBox WeekdayName(Weekday(CDate(Now)))

Borrowing from the above:
MsgBox WeekdayName(Weekday(CDate(Now)-18))

+ - number of days

@echo off :loop cls echo. set input= set week=+0 set /p input= Please enter the date (format: 20070101): if not defined input exit set /p week= Please enter the number of days to interval (format: +8(-8), default is 0): echo. >tmp.vbs echo wscript.echo WeekdayName(Weekday(CDate("%input:~0,4%-%input:~4,2%-%input:~6,2%")%week%)) for /f %%i in ('"cscript //nologo tmp.vbs"') do call echo %%i del tmp.vbs echo. pause goto loop

[ Last edited by zh159 on 2007-2-8 at 06:42 PM ]