Adding support for reading 3 of 9 Extended barcodes (containing lowercase characters) with GdPicture9

Microsoft .NET

3 of 9 barcodes are just about everywhere, and are one of the easiest barcodes to work with being widely supported by many SDK's. 3 of 9 originally supported only a subset of the ASCII character set, and later was extended to support the full range of characters. Often you will find 3 of 9 barcodes in the form of a font style that you can use in word processors, web applications, and other types of software. They can be copy and pasted. They are easy to draw, and most importantly, they are very easy to understand. You can read more on Wikipedia about it, but lets talk more about how GdPicture SDK deals with it.

code39-sample

GdPicture does support drawing 3 of 9 barcodes with the extended character set using the Barcode1DWriterType.Barcode1DWriterCode39Extended enumeration with Barcode1DWrite, but I found that it lacked the ability to read them using Barcode1DReaderDoScan. If you look deeper into the enumerations available for these methods, oddly enough both Barcode1DWriterType.Barcode1DWriterCode39 and Barcode1DWriterType.Barcode1DWriterCode39Extended exist for drawing the barcode, but only Barcode1DReaderType.Barcode1DWriterCode39 exists for reading when using Barcode1DReaderDoScan.

gI_78908_LOGO-GD9

Now, let me clarify before we look at a solution. GdPicture does technically read the barcode with extended characters, but it doesn't actually return the extended ASCII characters. Instead, it returns each uppercase character prefixed with the + character, which is a token indicating the character casing, such as the sign in a signed integer. In the examples below we will look at the most common scenario which is support for lower case characters, which are only part of the extended character set.

string threeOfNine    = "ABC123"; // normal character set
string threeOfNineExt = "abc123"; // extended character set

These are the raw values you would normally expect to see when reading 3 of 9 barcodes using a proper SDK. In GdPicture however, let us take a look at the difference when reading the extended barcodes.

string threeOfNine    = "ABC123";    // normal character set
string threeOfNineExt = "+A+B+C123"; // extended character set

This pattern is very consistent, so we can write a simple function to parse and return the correct character casing.

/// <devdoc>
/// This method is for GdPicture9's lack of support for *reading* the 3 of 9 Extended character set,
/// which allows for lowercase characters. GdPicture will still return a barcode value, but each lower
/// case character is preceded by + character to indicate the casing difference.
/// 
/// ie. TEst (raw value of *TEst*) would be returned as TE+S+T (raw value of *TE+S+T*)
/// </devdoc>
private static string Get3Of9ExtendedBarcodeValue(string s)
{
    var newValue = string.Empty;

    for (int i = 0; i < s.Length; i++)
        if (s[i] == '+')
            newValue += s[++i].ToString(CultureInfo.InvariantCulture).ToLower();
        else
            newValue += s[i];

    return newValue.Replace("+", string.Empty);
}

The method is pretty straight forward, iterating over each character and identifying the token. When the token is found we do a forward lookup in the array, which will be the actual character value, and we know to return the lowercase value. We also increment the loop counter at the same time since we are processing that character. Otherwise if no token is found, we simply return the character as is.

Simple!

Now, I have only written this function to account for the casing differences between the character sets because that was the scenario I needed to solve for the project I was working on. I could have used other barcode libraries, but we already had licensing for GdPicture and it is significantly faster than most of the libraries out there, and I tested quite a few. I might revisit this blog at a later time and write a new one discussing the other extended characters, but for now we will leave it there.

Happy coding!

64 Comments

  1. Pingback: kamagra uk

  2. Pingback: vidalista.pics

  3. Pingback: otclevitra.com

  4. Pingback: clomiphene Citrate

  5. Pingback: ekzistenczialnyj

  6. Pingback: Ïñèõîëîã, ïñèõîòåðàïåâò, ïñèõèàòð, ïñèõîàíàëèòèê

  7. Pingback: prednisone 20mg

  8. Pingback: clomid for sale

  9. Pingback: 75mg viagra

  10. Pingback: myprin92.ru

  11. Pingback: 0410.ru

  12. Pingback: atvip.ru

  13. Pingback: vigrakrs.com

  14. Pingback: why take latanoprost at night

  15. Pingback: sketchfab.com/female-cialis

  16. Pingback: 5yucMCMAAAAJ

  17. Pingback: instagram.com/korotkovlakanfreud

  18. Pingback: ofevinfo.wordpress.com

  19. Pingback: site

  20. Pingback: price of viagra per pill

  21. Pingback: samscainfo.wordpress.com

  22. Pingback: vidalforman.wordpress.com

  23. Pingback: Sochi-psiholog-Russia

  24. Pingback: who makes viagra pills

  25. Pingback: vardenafil 20mg

  26. Pingback: 100 mg viagra side effects

  27. Pingback: t.me/s/psy_chat_online

  28. Pingback: clomiphene 50mg ovulation

  29. Pingback: afinitor cost

  30. Pingback: Forum

  31. Pingback: fildena.homes

  32. Pingback: 439W6fo

  33. Pingback: psy

  34. Pingback: r2f.ru

  35. Pingback: xblx.ru

  36. Pingback: dilts.g-u.su

  37. Pingback: anatoliy-alekseyevich-derkach.ru

  38. Pingback: where to buy cheap toradol for sale

  39. Pingback: artane and coolock credit union

  40. Pingback: zanaflex for sciatica pain

  41. Pingback: cyproheptadine hydrochloride syrup ip side effects

  42. Pingback: street value of tizanidine 2mg

  43. Pingback: periactin sciroppo dosaggio

  44. Pingback: can you get generic ketorolac pills

  45. Pingback: baclofen compared to vicodin

  46. Pingback: azathioprine irregular heartbeat

  47. Pingback: maxalt wine

  48. Pingback: classe terapeutica piroxicam

  49. Pingback: how effective is meloxicam for pain

  50. Pingback: prospecto de lioresal

  51. Pingback: imdur pill

  52. Pingback: what are side effects of mobic

  53. Pingback: imuran proctitis

  54. Pingback: rizatriptan benzoate drug bank

  55. Pingback: can you take sumatriptan and paracetamol together

  56. Pingback: where can i buy generic pyridostigmine without dr prescription

  57. Pingback: diclofenac vs celebrex

  58. Pingback: cilostazol en insuficiencia cardiaca

  59. Pingback: can mebeverine be taken after food

  60. Pingback: indomethacin 75 sr

  61. Pingback: migraine injection imitrex

  62. Pingback: amitriptyline dose for sleep

  63. Pingback: mestinon tabs

  64. Pingback: elavil mgs

Leave a Comment