BarcodeDetector.md

BarcodeDetector

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: SpawnJSObject
Source: JSObjects/BarcodeDetector.cs
MDN Reference: BarcodeDetector on MDN

The BarcodeDetector interface of the Barcode Detection API allows detection of linear and two dimensional barcodes in images. https://developer.mozilla.org/en-US/docs/Web/API/BarcodeDetector

Constructors

Signature	Description
BarcodeDetector()	The BarcodeDetector() constructor creates a new BarcodeDetector object which detects linear and two-dimensional barcodes in images.
BarcodeDetector(BarcodeDetectorOptions options)	The BarcodeDetector() constructor creates a new BarcodeDetector object which detects linear and two-dimensional barcodes in images.
BarcodeDetector(SpawnJSObjectReference _ref)	Deserialization constructor

Methods

Method	Return Type	Description
GetSupportedFormats()	Task<List<string>>	The getSupportedFormats() static method of the BarcodeDetector interface returns a Promise which fulfills with an Array of supported barcode format types.
IsDefined()	bool	Checks if BarcodeDetector is defined in the global scope
Detect(Union<Blob, Element, ImageData, ImageBitmap, OffscreenCanvas> imageBitmapSource)	Task<Array<DetectedBarcode>>	The detect() method of the BarcodeDetector interface returns a Promise which fulfills with an Array of detected barcodes within an image. Receives an ImageBitmapSource as a parameter. This can be an element, a Blob of type image or an ImageData object.

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

• Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
• Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
• Async methods return Task<T> instead of Promise<T>
• Objects should be disposed with using statements
• Access via JS.Get<BarcodeDetector>(...) or constructor new BarcodeDetector(...)

Creating A Detector

// check compatibility
if (!("BarcodeDetector" in globalThis)) {
  console.log("Barcode Detector is not supported by this browser.");
} else {
  console.log("Barcode Detector supported!");

  // create new detector
  const barcodeDetector = new BarcodeDetector({
    formats: ["code_39", "codabar", "ean_13"],
  });
}

Getting Supported Formats

// check supported types
BarcodeDetector.getSupportedFormats().then((supportedFormats) => {
  supportedFormats.forEach((format) => console.log(format));
});

Detect Barcodes

barcodeDetector
  .detect(imageEl)
  .then((barcodes) => {
    barcodes.forEach((barcode) => console.log(barcode.rawValue));
  })
  .catch((err) => {
    console.log(err);
  });

See full example on MDN