Rust 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. Rust

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

let fmt = chilkat::Formats::new();
let json = chilkat::JsonObject::new();
let json_out = chilkat::JsonObject::new();

// Digits only.
let _ = json.update_string("payload.text", "00123456789012345678");
if fmt.qr_code("generate", &json, &json_out).is_err() {
    println!("{}", fmt.last_error_text());
    return;
}

println!("digits: mode {}, version {}", json_out.string_of("symbols[0].selectedEncoding.mode").unwrap_or_default(), json_out.int_of("symbols[0].selectedEncoding.version"));

// Upper-case letters, digits, space and - are all in the alphanumeric set.
let _ = json.update_string("payload.text", "ORDER-12345 LOT A7 SHELF 12-C");
if fmt.qr_code("generate", &json, &json_out).is_err() {
    println!("{}", fmt.last_error_text());
    return;
}

println!("upper case: mode {}, version {}", json_out.string_of("symbols[0].selectedEncoding.mode").unwrap_or_default(), json_out.int_of("symbols[0].selectedEncoding.version"));

// Lower-case letters are not, so the same text in lower case needs byte mode.
let _ = json.update_string("payload.text", "order-12345 lot a7 shelf 12-c");
if fmt.qr_code("generate", &json, &json_out).is_err() {
    println!("{}", fmt.last_error_text());
    return;
}

println!("lower case: mode {}, version {}", json_out.string_of("symbols[0].selectedEncoding.mode").unwrap_or_default(), json_out.int_of("symbols[0].selectedEncoding.version"));

// 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.
let _ = json.update_string("payload.text", "00123456789012345678");
let _ = json.update_string("encoding.qr.mode", "byte");
if fmt.qr_code("generate", &json, &json_out).is_err() {
    println!("{}", fmt.last_error_text());
    return;
}

println!("digits as bytes: mode {}, version {}", json_out.string_of("symbols[0].selectedEncoding.mode").unwrap_or_default(), json_out.int_of("symbols[0].selectedEncoding.version"));

// The four symbols, in the order they were made:

// 

// 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