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B4X Requires Chilkat v11.7.0+

QR Code Numeric, Alphanumeric and Byte Modes

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Demonstrates the QR encoding modes. Digits alone are stored in numeric mode, and text made only of digits, upper-case letters, space and $ % * + - . / : in alphanumeric mode. Both pack more characters into a symbol than byte mode, which is used for everything else. QrCode chooses the most compact mode the text allows, and the response reports it. A product code written in upper case therefore gives a smaller symbol than the same code in lower case.

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B4X
Dim success As Boolean = False

'  This example requires the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.

Dim fmt As ChilkatFormats
fmt.Initialize
Dim json As ChilkatJsonObject
json.Initialize
Dim jsonOut As ChilkatJsonObject
jsonOut.Initialize

'  Digits only.
json.UpdateString("payload.text", "00123456789012345678")
success = fmt.QrCode("generate", json, jsonOut)
If success = False Then
    Log(fmt.LastErrorText)
    Return
End If

Log("digits: mode " & jsonOut.StringOf("symbols[0].selectedEncoding.mode") & ", version " & jsonOut.IntOf("symbols[0].selectedEncoding.version"))

'  Upper-case letters, digits, space and - are all in the alphanumeric set.
json.UpdateString("payload.text", "ORDER-12345 LOT A7 SHELF 12-C")
success = fmt.QrCode("generate", json, jsonOut)
If success = False Then
    Log(fmt.LastErrorText)
    Return
End If

Log("upper case: mode " & jsonOut.StringOf("symbols[0].selectedEncoding.mode") & ", version " & jsonOut.IntOf("symbols[0].selectedEncoding.version"))

'  Lower-case letters are not, so the same text in lower case needs byte mode.
json.UpdateString("payload.text", "order-12345 lot a7 shelf 12-c")
success = fmt.QrCode("generate", json, jsonOut)
If success = False Then
    Log(fmt.LastErrorText)
    Return
End If

Log("lower case: mode " & jsonOut.StringOf("symbols[0].selectedEncoding.mode") & ", version " & jsonOut.IntOf("symbols[0].selectedEncoding.version"))

'  The mode can be named.  Byte mode can hold any text.  Naming a mode the text cannot use
'  (numeric for text with letters, for example) fails with conflictingOptions.
json.UpdateString("payload.text", "00123456789012345678")
json.UpdateString("encoding.qr.mode", "byte")
success = fmt.QrCode("generate", json, jsonOut)
If success = False Then
    Log(fmt.LastErrorText)
    Return
End If

Log("digits as bytes: mode " & jsonOut.StringOf("symbols[0].selectedEncoding.mode") & ", version " & jsonOut.IntOf("symbols[0].selectedEncoding.version"))

'  The four symbols, in the order they were made:

'  image

'  Sample output:

'  digits: mode numeric, version 1
'  upper case: mode alphanumeric, version 2
'  lower case: mode byte, version 3
'  digits as bytes: mode byte, version 2