QR Code Styling

Version

JavaScript library for generating QR codes with a logo and styling.

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If you have issues / suggestions / notes / questions, please open an issue or contact me. Let’s create a cool library together.

Examples



Installation

npm install qr-code-styling

Usage

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>QR Code Styling</title>
    <script type="text/javascript" src="https://unpkg.com/[email protected]/lib/qr-code-styling.js"></script>
</head>
<body>
<div id="canvas"></div>
<script type="text/javascript">

    const qrCode = new QRCodeStyling({
        width: 300,
        height: 300,
        type: "svg",
        data: "https://www.facebook.com/",
        image: "https://upload.wikimedia.org/wikipedia/commons/5/51/Facebook_f_logo_%282019%29.svg",
        dotsOptions: {
            color: "#4267b2",
            type: "rounded"
        },
        backgroundOptions: {
            color: "#e9ebee",
        },
        imageOptions: {
            crossOrigin: "anonymous",
            margin: 20
        }
    });

    qrCode.append(document.getElementById("canvas"));
    qrCode.download({ name: "qr", extension: "svg" });
</script>
</body>
</html>

React example (Codesandbox)

Angular example (Codesandbox)

React example (source)

Angular example (source)

Vue example (source)

API Documentation

QRCodeStyling instance

new QRCodeStyling(options) => QRCodeStyling

Param Type Description
options object Init object

options structure

Property Type Default Value Description
width number 300 Size of canvas
height number 300 Size of canvas
type string ('canvas' 'svg') canvas The type of the element that will be rendered
data string The date will be encoded to the QR code
image string The image will be copied to the center of the QR code
margin number 0 Margin around canvas
qrOptions object Options will be passed to qrcode-generator lib
imageOptions object Specific image options, details see below
dotsOptions object Dots styling options
cornersSquareOptions object Square in the corners styling options
cornersDotOptionsHelper object Dots in the corners styling options
backgroundOptions object QR background styling options
nodeCanvas node-canvas Only specify when running on a node server for canvas type, please refer to node section below
jsDom jsdom Only specify when running on a node server for svg type, please refer to node section below

options.qrOptions structure

Property Type Default Value
typeNumber number (0 - 40) 0
mode string ('Numeric' 'Alphanumeric' 'Byte' 'Kanji')
errorCorrectionLevel string ('L' 'M' 'Q' 'H') 'Q'

options.imageOptions structure

Property Type Default Value Description
hideBackgroundDots boolean true Hide all dots covered by the image
imageSize number 0.4 Coefficient of the image size. Not recommended to use ove 0.5. Lower is better
margin number 0 Margin of the image in px
crossOrigin string('anonymous' 'use-credentials') Set “anonymous” if you want to download QR code from other origins.
saveAsBlob boolean false Saves image as base64 blob in svg type, see bellow

When QR type is svg, the image may not load in certain applications as it is saved as a url, and some svg applications will not render url images for security reasons. Setting saveAsBlob to true will instead save the image as a blob, allowing it to render correctly in more places, but will also increase the file size.

options.dotsOptions structure

Property Type Default Value Description
color string '#000' Color of QR dots
gradient object Gradient of QR dots
type string ('rounded' 'dots' 'classy' 'classy-rounded' 'square' 'extra-rounded') 'square' Style of QR dots

options.backgroundOptions structure

Property Type Default Value
color string '#fff'
gradient object

options.cornersSquareOptions structure

Property Type Default Value Description
color string Color of Corners Square
gradient object Gradient of Corners Square
type string ('dot' 'square' 'extra-rounded') Style of Corners Square

options.cornersDotOptions structure

Property Type Default Value Description
color string Color of Corners Dot
gradient object Gradient of Corners Dot
type string ('dot' 'square') Style of Corners Dot

Gradient structure

options.dotsOptions.gradient

options.backgroundOptions.gradient

options.cornersSquareOptions.gradient

options.cornersDotOptions.gradient

Property Type Default Value Description
type string ('linear' 'radial') “linear” Type of gradient spread
rotation number 0 Rotation of gradient in radians (Math.PI === 180 degrees)
colorStops array of objects Gradient colors. Example [{ offset: 0, color: 'blue' }, { offset: 1, color: 'red' }]

Gradient colorStops structure

options.dotsOptions.gradient.colorStops[]

options.backgroundOptions.gradient.colorStops[]

options.cornersSquareOptions.gradient.colorStops[]

options.cornersDotOptions.gradient.colorStops[]

Property Type Default Value Description
offset number (0 - 1) Position of color in gradient range
color string Color of stop in gradient range

QRCodeStyling methods

QRCodeStyling.append(container) => void

Param Type Description
container DOM element This container will be used for appending of the QR code

QRCodeStyling.getRawData(extension) => Promise<Blob>

Param Type Default Value Description
extension string ('png' 'jpeg' 'webp' 'svg') 'png' Blob type on browser, Buffer type on Node

QRCodeStyling.update(options) => void

Param Type Description
options object The same options as for initialization

QRCodeStyling.download(downloadOptions) => Promise<void>

Param Type Description
downloadOptions object Options with extension and name of file (not required)

Promise returned will resolve into the data URI of the QR code image.

downloadOptions structure

Property Type Default Value Description
name string 'qr' Name of the downloaded file
extension string ('png' 'jpeg' 'webp' 'svg') 'png' File extension

Node Support

You can use this on a node server by passing through the node-canvas or jsdom object depending if your creating a non-svg or svg respectively. You must pass both if using imageOptions.saveAsBlob.

Calling getRawData in node will return a Buffer instead of a Blob.

const { QRCodeStyling } = require("qr-code-styling/lib/qr-code-styling.common.js");
const nodeCanvas = require("canvas");
const { JSDOM } = require("jsdom");
const fs = require("fs");

const options = {
    width: 300,
    height: 300,
    data: "https://www.facebook.com/",
    image: "https://upload.wikimedia.org/wikipedia/commons/5/51/Facebook_f_logo_%282019%29.svg",
    dotsOptions: {
        color: "#4267b2",
        type: "rounded"
    },
    backgroundOptions: {
        color: "#e9ebee",
    },
    imageOptions: {
        crossOrigin: "anonymous",
        margin: 20
    }
}

// For canvas type
const qrCodeImage = new QRCodeStyling({
    nodeCanvas, // this is required
    ...options
});

qrCodeImage.getRawData("png").then((buffer) => {
  fs.writeFileSync("test.png", buffer);
});

// For svg type
const qrCodeSvg = new QRCodeStyling({
    jsdom: JSDOM, // this is required
    type: "svg",
    ...options
});

qrCodeSvg.getRawData("svg").then((buffer) => {
  fs.writeFileSync("test.svg", buffer);
});

// For svg type with the inner-image saved as a blob
// (inner-image will render in more places but file will be larger)
const qrCodeSvgWithBlobImage = new QRCodeStyling({
    jsdom: JSDOM, // this is required
    nodeCanvas, // this is required
    type: "svg",
    ...options,
    imageOptions: {
        saveAsBlob: true,
        crossOrigin: "anonymous",
        margin: 20
    }
});

qrCodeSvgWithBlobImage.getRawData("svg").then((buffer) => {
  fs.writeFileSync("test_blob.svg", buffer);
});

License

MIT License. Copyright (c) 2021 Denys Kozak