Go Requires Chilkat v11.7.0+

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. Go

    success := 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.
    sbText := chilkat.NewStringBuilder()
    sbText.Append("Gr\u00fc\u00dfe aus M\u00fcnchen")
    sbText.Decode("json","utf-8")

    json := chilkat.NewJsonObject()
    json.UpdateSb("payload.text",sbText)
    json.UpdateString("output.path","qa_output/qr_utf8.png")
    json.UpdateBool("output.overwrite",true)
    json.UpdateString("output.return","none")

    fmt := chilkat.NewFormats()
    jsonOut := chilkat.NewJsonObject()
    success = fmt.QrCode("generate",json,jsonOut)
    if success == false {
        fmt.Println(fmt.LastErrorText())
        sbText.DisposeStringBuilder()
        json.DisposeJsonObject()
        fmt.DisposeFormats()
        jsonOut.DisposeJsonObject()
        return
    }

    //  17 characters, three of which take two bytes in UTF-8.
    fmt.Println("characters: ", sbText.Length())
    fmt.Println("bytes encoded: ", jsonOut.IntOf("symbols[0].payloadBytes"))
    fmt.Println("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 {
        fmt.Println(fmt.LastErrorText())
        sbText.DisposeStringBuilder()
        json.DisposeJsonObject()
        fmt.DisposeFormats()
        jsonOut.DisposeJsonObject()
        return
    }

    fmt.Println("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

    sbText.DisposeStringBuilder()
    json.DisposeJsonObject()
    fmt.DisposeFormats()
    jsonOut.DisposeJsonObject()