Terminal output

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A command-line tool can show a QR code in the terminal, for instance to set up an authenticator app or to open a URL on a phone. The console renderer draws the code with the Unicode block characters █, ▀ and ▄, two rows of modules per line of text:

var qrCode = QRCode.Create("HELLO WORLD", ErrorCorrectionLevel.H);
var microQr = QRCode.CreateMicroQR("12345", ErrorCorrectionLevel.L);

qrCode.WriteToConsole();
var text = qrCode.ToConsoleString();

var microText = microQr.ToConsoleString(new QRCodeConsoleOptions
{
    QuietZoneModules = 1,
    ModuleWidth = 2,
    ModuleHeight = 2, // 2x bigger output that can look more square on many terminals
});

Assert.Equal("""

      ██████████████  ██  ██
      ██          ██  ████
      ██  ██████  ██  ██
      ██  ██████  ██
      ██  ██████  ██  ██████
      ██          ██    ████
      ██████████████  ██
                        ████
      ████    ██████    ████
        ██  ██      ████
      ████████          ████

    """, microText, ignoreLineEndingDifferences: true);

WriteToConsole writes to Console.Out, WriteTo to any TextWriter, and ToConsoleString returns the text.
The blocks are drawn in the color of the text, for the dark modules. On a terminal with a dark background, set InvertColors: the blocks then draw the light modules and the quiet zone, so that the code is dark on light.
QuietZoneModules is 2 by default. With the default sizes, a module is one character wide and half a line high, which is about square in most terminals. ModuleWidth repeats each module in characters and ModuleHeight in half lines: increase both together to get a larger code that stays square.
The terminal must use a font that has the block characters, and display the output in UTF-8.
The output must fit in a string: options that make it larger throw an ArgumentOutOfRangeException.

The console renderer draws QR codes only, not linear barcodes.