VB.NET Requires Chilkat v11.7.0+
VB.NET
QR Code with Non-English Text (UTF-8 and ECI)
See more QR Code Examples
Demonstrates text outside ASCII. QrCode always stores text as UTF-8 bytes, which is what phones expect. A QR code can also say so explicitly with an ECI header: setting encoding.eci to 26 declares the bytes to be UTF-8, for readers that would otherwise assume another character set. The header costs a little space, and a few older readers do not understand it, so it is off by default.Chilkat VB.NET Downloads
Dim success As Boolean = False
' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.
' The text is "Gruesse aus Muenchen" written with u-umlaut and sharp s. It is given here with
' JSON escapes only so that this source is plain ASCII. Decode turns the escapes into characters.
Dim sbText As New Chilkat.StringBuilder
sbText.Append("Gr\u00fc\u00dfe aus M\u00fcnchen")
sbText.Decode("json","utf-8")
Dim json As New Chilkat.JsonObject
json.UpdateSb("payload.text",sbText)
json.UpdateString("output.path","qa_output/qr_utf8.png")
json.UpdateBool("output.overwrite",True)
json.UpdateString("output.return","none")
Dim fmt As New Chilkat.Formats
Dim jsonOut As New Chilkat.JsonObject
success = fmt.QrCode("generate",json,jsonOut)
If (success = False) Then
Debug.WriteLine(fmt.LastErrorText)
Exit Sub
End If
' 17 characters, three of which take two bytes in UTF-8.
Debug.WriteLine("characters: " & sbText.Length)
Debug.WriteLine("bytes encoded: " & jsonOut.IntOf("symbols[0].payloadBytes"))
Debug.WriteLine("ECI header: " & jsonOut.HasMember("symbols[0].selectedEncoding.eci"))
' Without an ECI header (qa_output/qr_utf8.png):
'
' The same text with an ECI header declaring UTF-8.
json.UpdateInt("encoding.eci",26)
json.UpdateString("output.path","qa_output/qr_utf8_eci.png")
success = fmt.QrCode("generate",json,jsonOut)
If (success = False) Then
Debug.WriteLine(fmt.LastErrorText)
Exit Sub
End If
Debug.WriteLine("with encoding.eci = 26, ECI header: " & jsonOut.HasMember("symbols[0].selectedEncoding.eci") & ", value " & jsonOut.IntOf("symbols[0].selectedEncoding.eci"))
' With the ECI header (qa_output/qr_utf8_eci.png). Both scan as the same text:
'
' Sample output:
' characters: 17
' bytes encoded: 20
' ECI header: False
' with encoding.eci = 26, ECI header: True, value 26