0

We are using bar code scanners in our application to scan bar codes. Generally, when the ISBN bar code is scanned it return the following bunch of keys when scanning ISBN: 97887021006268

  • LeftCtrl
  • B
  • LeftShift
  • M
  • D9
  • D7
  • D8
  • D8
  • D7
  • D0
  • D2
  • D1
  • D0
  • D6
  • D2
  • D6
  • D8
  • LeftCtrl
  • C

LeftCtrl+B combination is the preamble and tells us that it we are starting to read identifying number. LeftCtrl+C combination is the postamble and tells us that we are finishing to read identifying number. LeftShift+M combination tells us that we read barcode type. Based on that information, after scanning bar code I can automatically search for book with the related ISBN. We are using our own bar code reader library where we can recognize ISBN, Code39 and I2Of5.

Now, our client both new bar code scanners that are the keyboard scanners. After scanning the same ISBN, we can see that it does not contains, preamble, and postamble, as good as code for returning barcode type. Instead we got only numbers and Return key at the end:

  • D9
  • D7
  • D8
  • D8
  • D7
  • D0
  • D2
  • D1
  • D0
  • D6
  • D2
  • D6
  • D8
  • Return

In such case I cannot automatically recognize what is the type of bar code and even recognize whether it was bar code scanned - for instance I cannot automatically search for To resolve the problem I am thinking about the user control where user with:

  • TextBox to which will be identifying number scanned
  • RadioButton with options (ISBN, Code39, I2Of5)
  • Button responsible for further processing based on selected RadioButton option an value in TextBox and

I would like to ask whether there is other (better) solution.

Improve this question
4
  • I dont see why you should be caring about the barcode type. Surely the value is all that matters as this will be what provides a lookup in your DB. Are you saying you have entries with the same barcode value but are different because of there barcode type? this sounds like a bad approach to me Commented Oct 19, 2011 at 8:53
  • Currently I can scan ISBN, Code39 or I2OF5. When I scan ISBN the application should search for books, when I scan Code39 or I2OF5 application should search for orders (orders also have bar codes). So there are different scenarios undertaken based on the type of bar code Commented Oct 19, 2011 at 9:02
  • Well the only way to go then is to get more input from the user. I would suggest a set of radio buttons to allow easy selection of the type of object they are looking for. So options for "Books" or "Orders" would probably be best. Then you search the correct database. Essentially, as you have pointed out, is the new barcode data just doesn't have enough information and you cannot change that without the customer changing there equipment. Commented Oct 19, 2011 at 9:29
  • Yes, User cannot change the equipment unfortunately Commented Oct 19, 2011 at 9:35

2 Answers 2

Reset to default
1

There's several hints you can code for. If you are scanning a real book, you'll get an EAN13+5 Bookland EAN code. If you're using a different code type (like your example) you'll get just the 13 digits. Check the length == 13 or length == 18.
ISBNs start with 978 (or 979, eventually) and end with a MOD 10 checksum. So you could check the scan value 

/^(97[8|9]\d{10})5(\d{4})$/

for US priced books. The last digit before the price is the checksum. That should give you a good indication that you're working with an ISBN.
I've found it's better to code that into the server then depend on the user for correct input.

Improve this answer
Sign up to request clarification or add additional context in comments.

Comments

0

you should be able to get the info you're missing from two very big buttons "scan book" and "scan order" so the user clicks one of the very big buttons and you know what to look for.

it goes like this:

  1. user grabs whatever they want to scan
  2. user clicks a very big button "scan book" or "scan order" (here you get the code type you no longer have)
  3. user performs the scan
  4. you do what you need to do with the scanned number
Improve this answer

Comments

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.