Remove characters/limit entry with Script

[DrNikon224]

I am building a database to track equipment loans to college students. I am planning on using their student ID (with a magnetic stripe) to lookup their info each time they check something out. The only problem is that the magnetic stripe is encoded with more data than just their student number. More specifically, the first 9 characters are the ID number, followed by other codes used by the university.

I want to keep only the first 9 characters entered into the field by the card reader (the reader emulates typing on the keyboard - the computer doesn't know the difference). How can I tell FileMaker to remove anything after the ninth character, or to simply not allow typing after the ninth character in that field? (I tried setting the max characters to 9 in the validation, but it still lets me enter more than 9 and gives me an error when i try to move on.)

Is there any way to accomplish this? I've spent about 20 hours on this system for the school, and was just now informed of this complicating factor....

Needless to say, I don't want to loose everything I've done just because we can't get the Student Number off the ID card.

Suggestions welcome!!

[jasonwood]

You could use two fields. One for input, and one for display and use. The input field takes all characters. The display field is a calculation that takes the first 9 characters from the input field.

You can put the fields on top of each other on the layout (display field on top), then disallow entry into the display field so that when you click in the field, it goes back to the input field and allows you to swipe the card.

If a script or a tab order is taking you to the input field...then I'm not sure you would even have to deny data entry into the display field... you might want to click into the display field any ways to copy the student number.

[laker_42]

I am not sure what type the information is coming from the code reader but have you tried using the Left(Text,Number) or Truncate(Number,precision) functions? They should do what you are asking to do. Read the info into an input field. You can then make the ID field a calculation and use either of these functions. It should work for you.

John

[DrNikon224]

I thought about adding a field like that, but that would require swiping each student's card when they are added to the database. The students are added at the beginning of each semester from class rosters. I won't have their cards to swipe when I put them in. Using the two-field method, though, I would have to have something to put into the student's "input" field so I could use a swipe to find the student's record in the future.

I was just poking around in the scriptmaker, and would it be possible for me to have a script enter all the data into the student number field, cut it, and insert a calculated result (or something along those lines)?

[jasonwood]

I don't understand how two fields would be a problem...

You've got two database files, one for students, one for checkouts.

The students database is created at the beginning of the year, it has a studentNumber field... and a checkout record is created in the checkouts database every time they check something out.

The two relate together using the studentNumber field and the studentNumberCalculated field from the checkouts database.

Even if this isn't the method you're using, you have to think of the input field as simply a place where data is entered, be it through an import or a swipe... it still works if you're just typing in a 9 digit student number. Then the calculated field is the field you actually USE for relationships, scripts, etc.

[DrNikon224]

Is there a way to make the display field update in find mode? The only problem that I might run into doing it using the two different fields, is that some of the code on the card changes (there is a 'issue number' embedded in the code, so if a student loses his/her card, and gets a new one, the old one becomes invalid in the university's system and no one else can use it), and I might run into trouble using a swipe to lookup information if the swipe information doesn't exactly match the data in the swipe field.

ANOTHER OPTION??: Could I use a global field as a data holder, and have part of my card reader post-amble (a script it runs after entering the swiped information) perform the calculation and cut/paste it into the 9-digit field?

[]Pre-amble[]

Go to field Global Swipe

Clear field Gloabal Swipe

[]

[]Swipe Card[]

Enters data string into Global Swipe field

[]

[]Post-Amble[]

Insert Calculated Result {Left (Global Swipe, 9)}

Clear Field Calculated Result

[]

I just took the time to test this...and it seems to work fine...can anyone see any problems with it?

I'm DrNikon224 on AIM if anyone wants to chat realtime about my seemingly complex problem.

thanks,

[DrNikon224]

...further testing reveals that a Global Swipe field is not needed, I can perform the LeftText function on the same field (ie; take data from Student ID, and put it back in Student ID).

I can also run a second text function, RightText, after the LeftText to remove the 3 0's at the beginning of all the Student ID #'s!!!

I think i've finally got it figured out!

Thanks all,

[jasonwood]

What kind of system are you running?

Just wondering if it's a Mac cause I've been trying to find a Mag Stripe reader that allows a "Command" postamble.

[DrNikon224]

I am planning on using the IDTECH MiniMag mag-stripe scanner (can be found on lltproducts.com). According to LLT, this scanner will allow the command key in the post amble.

[jasonwood]

You're gonna be glad I asked...

This is what a technical representative from IDTECH said when they replied to my email a couple weeks ago:

------------

Hi Jason,

Our a USB Mag Stripe reader is compatible with Mac. You are able to specify a string of printable characters as preamble or postamble. However it won't be able to do a "Apple

Keystroke" in Pre or Post-amble. By the way, the reader can only be programmed on a PC AT through our USB configuration software. After it's been programmed, you can plug it back to

Mac.

-----------

Double check with LLT. I'd tend to believe the manufacturer first, but maybe they have a workaround.

Let me know how this goes!!

[DrNikon224]

Jason,

I emailed the LLT people, and this is what they told me:

------------------------------------------------------------------------------------------------

Ctrl key (preamble/post amble) on a PC is definitely not a problem.

And Tech support said that he should have no problem with the apple/command

key on a Macintosh either (as long as he is going USB)--but they do not have

a mac there to test because they do not support mac.

Let me know if this makes sense.

--------------------------------------------------------------------------------------------------

After reading this, I decided to double check with the manufacturer just to be extra sure, because I'm working on a state budget, and it's a bit of a hassle to return/exchange things.

I'll post their reply if their answer differs from yours at all.

Thanks for the heads up!

[jasonwood]

I don't think you understand... you said you were planning on using an IDTECH reader... the e-mail I posted above IS from IDTECH (the manufacturer). I contacted them a few weeks ago for the same reason...

[DrNikon224]

I've found a card reader that does what we want.

look at the attached file, or go to http://www.magtek.com

they sell a reader that can send a pre-card and a pre-track character, and post-track/card character.

best of luck to ya.

PS USB Swipe.zip