.NET Core C# 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. .NET Core C#

bool 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.
Chilkat.StringBuilder sbText = new Chilkat.StringBuilder();
sbText.Append("Gr\u00fc\u00dfe aus M\u00fcnchen");
sbText.Decode("json","utf-8");

Chilkat.JsonObject json = 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");

Chilkat.Formats fmt = new Chilkat.Formats();
Chilkat.JsonObject jsonOut = new Chilkat.JsonObject();
success = fmt.QrCode("generate",json,jsonOut);
if (success == false) {
    Debug.WriteLine(fmt.LastErrorText);
    return;
}

//  17 characters, three of which take two bytes in UTF-8.
Debug.WriteLine("characters: " + Convert.ToString(sbText.Length));
Debug.WriteLine("bytes encoded: " + Convert.ToString(jsonOut.IntOf("symbols[0].payloadBytes")));
Debug.WriteLine("ECI header: " + Convert.ToString(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) {
    Debug.WriteLine(fmt.LastErrorText);
    return;
}

Debug.WriteLine("with encoding.eci = 26, ECI header: " + Convert.ToString(jsonOut.HasMember("symbols[0].selectedEncoding.eci")) + ", value " + Convert.ToString(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