A simple qr-code scanner for react
This is a simple qr-code scanner component for react. Check out a simple demo here!
Installing
A step by step series guide to setup this component.
Start a react project
- For Vite react JavaScript starter template, run the following command:
npm create vite@latest my-qr-code-scanner-application -- --template react
- For Vite react TypeScript starter template, use the command:
npm create vite@latest my-qr-code-scanner-application -- --template react-ts
Install the package with npm
npm i react-simple-qr-code-scanner
Demos
Basic
The code snippet below demonstrates the basic usage of the QR code scanner component:
import { QrCodeScanner } from "react-simple-qr-code-scanner";
function App() {
return (
<QrCodeScanner
onResult={(result, rawResult) => {
console.log(result);
}}
Errors={(error) => {
console.log(error);
}},
facingMode={"environment"} // Or "user"
/>
);
}Custom styling
The code snippet below demonstrates how to customize the styling of the QR code scanner component:
import { QrCodeScanner } from "react-simple-qr-code-scanner";
const App = () => (
<div style={{ width: "50vw" }}>
<QrCodeScanner
onResult={(result) => {
console.log(result);
}}
>
{(videoElement) => (
<div
style={{
borderColor: "rgb(147 197 253)",
borderWidth: "4px",
width: "100%",
}}
>
<video ref={videoElement} style={{ width: "100%", height: "100%" }} />
</div>
)}
</QrCodeScanner>
</div>
);Validating qr code data
Currently, the component only supports Zod as a validator (or custom validators) for QR code data. See the example below:
import { QrCodeScanner } from "react-simple-qr-code-scanner";
import { ZodQrCodeDataValidator } from "react-simple-qr-code-scanner/validators";
import { z } from "zod";
const QrCodeData = z.object({
foo: z.string(),
bar: z.number().min(500, "bar must be greater than 500"),
});
function App() {
return (
<>
<QrCodeScanner
validate={(data) => ZodQrCodeDataValidator(data, QrCodeData)}
onResult={(result) => {
console.log(result); // Result will be of the type {foo: string; bar: number;}
}}
onError={(error) => {
console.log(error); // Displays an error message if 'bar' is less than 500
}}
/>
</>
);
}Validating qr code data with custom validation
In this example, custom validation is performed on the QR code data:
import { QrCodeScanner } from "react-simple-qr-code-scanner";
type QrCodeData = {
foo: string;
bar: number;
};
function App() {
return (
<>
<QrCodeScanner
validate={(data) => {
if (!data || data == null || typeof data != "object")
throw new Error("data is required");
if (
!Object.prototype.hasOwnProperty.call(data, "foo") ||
!("foo" in data) ||
data.foo == null ||
typeof data.foo != "string"
)
throw new Error("foo is required");
if (
!Object.prototype.hasOwnProperty.call(data, "bar") ||
!("bar" in data) ||
data.bar == null ||
typeof data.bar != "number"
)
throw new Error("bar is required");
return { foo: data.foo, bar: data.bar };
}}
onResult={(result) => {
console.log(result); // Result will be of type QrCodeData due to the validation defined in the 'validate' property
}}
onError={(errorScan) => {
console.log(errorScan.message); // Log the validation error messages
}}
/>
</>
);
}Updating to version 2.0.0 (or higher)
Starting from version 2.0.0, the onResult function now takes two parameters. The rawResult parameter represents the original result.
Examples
Before 2.0.0:
import { QrCodeScanner } from "react-simple-qr-code-scanner";
function App() {
return (
<QrCodeScanner
onResult={(result) => {
console.log(result.getText());
}}
/>
);
}Since Version 2.0.0:
import { QrCodeScanner } from "react-simple-qr-code-scanner";
function App() {
return (
<QrCodeScanner
onResult={(result, raw) => {
console.log(result); // Returns the text, parsing and validating it if necessary.
console.log(raw.getText()); //
}}
/>
);
}License
This project is licensed under the MIT License License. See the LICENSE file for more details.