Encoding UTF-8 characters in QR codes

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1

Task

In order to display umlauts correctly in QR codes (and data matrix codes), they must be UTF8-encoded.

Solution

Current List & Label versions

Use the designer function UTF8Encode$.
Example: Barcode(UTF8Encode$("ÄÖÜ"),"QRCode")

List & Label versions 27 and smaller

The QR code itself has no fixed encoding. In order to make sure to UTF-8 encode the contents you should pass them byte-by-byte - this circumvents any problems between passing the content, rendering it as QR code and scanning it. A designer extension function that handles this job would be wired up like this:

image

The evaluation code would read:

private void designerFunction1_EvaluateFunction(object sender, EvaluateFunctionEventArgs e)
{
    string input = e.Parameter1.ToString();

    var utf8 = Encoding.UTF8;
    byte[] utfBytes = utf8.GetBytes(input);
    StringBuilder barcodeContent = new StringBuilder();
    foreach (byte b in utfBytes)
    {
        barcodeContent.AppendFormat("~d{0:000}", b);
    }
    e.ResultValue = barcodeContent.ToString();
    e.ResultType = LlParamType.String;
}

Then use EncodeAsUTF8(<actual content>) for your barcode’s content. The same procedure would work for the DataMatrix barcode as well.

If there are no designer functions available in your programming language you can of course pass a variable/field with the converted content (~d...~d..., where ... represents the UTF8 bytes).