Reading and writing binary strings

[gildas-lormeau]

Binary strings are strings used to store binary data, see here for more information: https://developer.mozilla.org/en-US/docs/Web/API/DOMString/Binary

The implementation of the classes BinaryStringReader and BinaryStringWriter below allows you to handle them in zip.js.

import { Reader, Writer } from "@zip.js/zip.js";

class BinaryStringReader extends Reader {

	constructor(binaryString) {
		super();
		this.binaryString = binaryString;
	}

	async init() {
		super.init();
		this.size = this.binaryString.length;
	}

	async readUint8Array(offset, length) {
		const result = new Uint8Array(length);
		for (let indexCharacter = 0; indexCharacter < length; indexCharacter++) {
			result[indexCharacter] = this.binaryString.charCodeAt(indexCharacter + offset) & 0xFF;
		}
		return result;
	}
}

class BinaryStringWriter extends Writer {

	constructor() {
		super();
		this.binaryString = "";
	}

	async writeUint8Array(array) {
		super.writeUint8Array(array);
		for (let indexCharacter = 0; indexCharacter < array.length; indexCharacter++) {
			this.binaryString += String.fromCharCode(array[indexCharacter]);
		}
	}

	getData() {
		return this.binaryString;
	}
}