Weird error when calculating difference between dates

[AngelaWatson]

Hi, I have seen posts on how to calculate the difference between two dates, but don't see mention of the error I am seeing.

Code in total field's custom calculation:

Custom calculate script

(function () {

var sStart = getField("jailIn1").valueAsString;

var sEnd = getField("jailOut1").valueAsString;

var dStart, dEnd, diff;

if(sStart && sEnd) {

dStart = util.scand("m/d/yyyy", sStart);

dEnd = util.scand("m/d/yyyy", sEnd);

//Below two lines are miscalc-ing for March 1-9, 2020 as start dates - drops a day if total is more than 9

diff = dEnd.getTime() - dStart.getTime();

event.value = Math.floor(diff / 864e5)+1;

} else {

event.value = "";

}

})();

(Editor made changes, can't tell if it broke the code)

This calculates the number of days between my in and out dates. (If they are the same date, the total should be 1.) 

It works fine in Edge, but not Acrobat.  In Acrobat it works EXCEPT if the in date is March 1-9, 2020 AND the total days is supposed to be 9 or more. In that narrow case, the total days low by 1.  See attached example.

I can't figure out why Acrobat is having an issue with these specific dates.  I tried adjusting the date formats, but the error persists.  Any suggestions welcome.

[try67]

Where's the dateDiff function?

[try67]

The code you posted is not what's used in the file...

[AngelaWatson]

Sorry, I can't access this site from work, so had to email the code to my phone - the site editor made changes when I tried to post.  Thanks to my dyslexia, there is no way I can accurately proof code between my phone and laptop.

The code is the typical code posted to sites like this - please refer to the attached file.  The code works just fine - except for this narrow range of start dates.

I tried switching to dateDiff, but that threw an error, saying dateDiff doesn't exist.  That function is included with Adobe Sign, but doesn't seem to work with plain ol' Acrobat Pro.

I'm considering adding code to look for the problem dates, and skipping the calculation if one of the problem dates is entered.... but I have hundreds of fields to update, so I want to know if there's a better solution before doing all that work.

I don't know if any other dates have this problem.  I checked 2019-2022, which is the typical date range my users would enter.

[try67]

Adobe Sign does not support scripting at all. There's no built-in function named dateDiff in it, or in Acrobat, which is why your code doesn't work.

[AngelaWatson]

Sigh... the attached file had both fields I tried to get to work, and fields with the original code.  The first field included two extra lines of code - trying to get dateDiff to work.  All of the rest of the fields just have the original code.

Let's try this again (Attached is a copy with the dateDiff code commented out.).  The code at issue is:

// Custom calculate script
(function () {

var sStart = getField("jailIn2").valueAsString;
var sEnd = getField("jailOut2").valueAsString;
var dStart, dEnd, diff;

if(sStart && sEnd) {
dStart = util.scand("m/d/yyyy", sStart);
dEnd = util.scand("m/d/yyyy", sEnd);
diff = dEnd.getTime() - dStart.getTime();
event.value = Math.floor(diff / 864e5)+1;
} else {
event.value = "";
}

})();

[try67]

Works fine for me. I clear the second field, then re-enter "03/9/2020" into it and the result is 9.

[AngelaWatson]

I said it works in Edge, but not in Acrobat Pro or Adobe Reader (latest versions).

What software/version are you using?

This is what I see when entering 3/1/2020 and 3/9/2020... 8 days instead of 9.

Any ideas why it is not working for multiple people on my end, but is on yours?

[try67]

I used both Reader DC and Acrobat XI Pro, and got the same results in both. I can try it in Acrobat DC Pro later on.

[Bernd Alheit]

I get 9 days in Adobe Acrobat DC.

[AngelaWatson]

Thanks so much for testing this out.

I went back and found more staff to test this with - where I'm physically present so I can confirm the way this is working.

It turns out that the issue is in the the latest version of Acrobat Pro - yet only some users see this error.  I can't determine what is triggering the error, but it is consistent - the calculation either alway works, or always breaks. Yes, this calculation script is working differently for users with the exact same version of Pro.  Since I can't force staff to use Reader vs. Pro, I'll have to add something to the calculation to look for the problem dates, then let users enter the total manually.  (Or just remove the calculations entirely.)

Thanks again!

[Bernd Alheit]

What does you mean with latest version?

[AngelaWatson]

Acrobat Pro 22022.001.20085.

And someone just said they saw the problem in Reader 2022.001.20085 - though they have both Reader and Pro on their laptop.  I'm not seeing the issue with anyone that has this version of Reader only (no Pro installed).

So, can't use this code - can't trace what's causing the error.  I'll probably remove the code vs. trying to program around these dates.

[try67]

One possible cause I can think of for this type of error is caused by the way you're calculating the difference between the two dates, ie, dividing the number of milliseconds by the number of ms per day. The issue with doing it like that is that number is not always the same. Namely, when there's a change to daytime savings an extra hour is added to that day (or reduced, when changed back) and it will throw off this type of calculation if you don't account for that. Now, the dates you mentioned do not correspond with the usual time when this happens, so I'm not sure that's the issue here, but it might be, depending on your location.

The way to account for it is to use Math.round, instead of Math.floor, as that will round the number either up or down to the nearest integer.

[try67]

Another option is to calculate the difference between the two dates using a loop, starting from the first one and adding one day until reaching the last one. That circumvents this issue entirely.

[Bernd Alheit]

The actual version for Windows is 22.001.20117

[AngelaWatson]

Okay, so my IT staff is wrong - the Adobe site says 22.001.2011x is the latest version. It will take me a few days to have that installed.

Thanks for the suggestion about programming a loop to do the calcuations, and that the current code doesn't account for time shifts.  Unfortunately, I am not a programmer.  I'll have to find an online class or tutorial to figure that out. (Which I will do - I just had no idea what direction to go in before.)

It might be a few  weeks, but I'll post again once I work out replacement code.

[try67]

Try this code:

var diff = 0;
while (util.printd("mm/dd/yyyy", dStart)!=util.printd("mm/dd/yyyy", dEnd)) {
	dStart.setDate(dStart.getDate()+1);
	diff++;
}
if (diff>0) diff++;

Edited: Fixed a small error in the code...