Easy way to do a DATE comparison?

[Scott Wolfington]

Hey all,

Is there an easy way to do a date comparison if the dates are in
string format? (ie. Is "01/01/2001" less than "02/14/2001")

I'm afraid the long answer is to parse out each date, add the date parts
to a SYSTEMTIME struct, convert the SYSTEMTIME struct to a FILETIME
struct, and then use the CompareFileTime Windows API function to
get my answer.

Any ideas would be much appreciated. Thanks!

Scott



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Scott Wolfington
http://www.boogietools.com



[This message has been edited by Scott Wolfington (edited March 05, 2003).]

[Egbert Zijlema]

Scott,

Use a Julian function. See the download section of my website.


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[Scott Turchin]

I emailed you my checkreg.bas file, it has everything you will need.




Scott


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Scott
mailto:[email protected][email protected]</A>

[Eric Pearson]

Scott W. --

All of those suggestions will work, or, if you want to keep it simple, you could just
write a function that converts the strings to a format that can be compared directly.

01/01/2001 --> 20010101
02/14/2001 --> 20010214

If you place the elements of the date in "descending" order a normal string comparison
can be performed.

This logic can be extended to compare date/times too, using YYYMMDDHHMMSS. Be careful
if you use VAL to convert a date/time in that format to a numeric value, because it
will overflow a LONG in the year 2147. Use a DWORD instead. But there's really no
reason to use VAL when the strings can be compared directly, unless using VAL and
a numeric comparison is faster than a string comparison. (I haven't checked.)

-- Eric
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Perfect Sync: Perfect Sync Development Tools
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[This message has been edited by Eric Pearson (edited January 18, 2001).]

[Fred Oxenby]

Do yourself a favour....
Create your date-routine around 'VARIANT TIME' (same as VB-date/time)
and you will be able to 'do math' on them.
Add a day,second or year...


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Fred
mailto:[email protected][email protected]</A>
http://www.oxenby.se

[Scott Wolfington]

Thanks everyone for your prompt responses. I definitely have some stuff
to try out now. Right off the bat, I like Eric's approach the best.
It seems the quickest, although I haven't spent much time poking holes
in this approach. Doesn't seem like there are any though.

Thanks for the email Scott T.

Regards,
Scott


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Scott Wolfington
http://www.boogietools.com


[This message has been edited by Scott Wolfington (edited March 05, 2003).]