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C++ Requires Chilkat v11.7.0+

QR Code Numeric, Alphanumeric and Byte Modes

See more QR Code Examples

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.

Chilkat C++ Downloads

C++
#include <CkFormats.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkFormats fmt;
    CkJsonObject json;
    CkJsonObject jsonOut;

    //  Digits only.
    json.UpdateString("payload.text","00123456789012345678");
    success = fmt.QrCode("generate",json,jsonOut);
    if (success == false) {
        std::cout << fmt.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "digits: mode " << jsonOut.stringOf("symbols[0].selectedEncoding.mode") << ", version " << jsonOut.IntOf("symbols[0].selectedEncoding.version") << "\r\n";

    //  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) {
        std::cout << fmt.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "upper case: mode " << jsonOut.stringOf("symbols[0].selectedEncoding.mode") << ", version " << jsonOut.IntOf("symbols[0].selectedEncoding.version") << "\r\n";

    //  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) {
        std::cout << fmt.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "lower case: mode " << jsonOut.stringOf("symbols[0].selectedEncoding.mode") << ", version " << jsonOut.IntOf("symbols[0].selectedEncoding.version") << "\r\n";

    //  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) {
        std::cout << fmt.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "digits as bytes: mode " << jsonOut.stringOf("symbols[0].selectedEncoding.mode") << ", version " << jsonOut.IntOf("symbols[0].selectedEncoding.version") << "\r\n";

    //  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
    }