JavaScript - convert Blob object to Uint8Array object (to bytes array)

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// Warning: Blob arrayBuffer() method appeared in the major web browser around 2019-2020 (in Deno v1.0 (2020), in Node.js v15.7.0 (2021)).


const toArray = (blob, callback) => {
    const promise = blob.arrayBuffer();
    promise.then((buffer) => callback(new Uint8Array(buffer)));
};


// Usage example:

const blob = ...;  // Blob object

toArray(blob, (array) => {
    console.log(`array.length=${array.length}`);
    console.log(`array[0]=${array[0]}`);
    console.log(`array[1]=${array[1]}`);
    console.log(`array[2]=${array[2]}`);
    console.log(`...`);
});


// See also:
//   1. https://dirask.com/snippets/JavaScript-convert-Blob-object-to-Uint8Array-object-to-bytes-array-1GMYbp