Code Completion 8 Challenges

JavaScript Binary Data — Code Completion

Practice ArrayBuffer, TypedArrays, and DataView operations.

Create an 8-byte buffer

javascript Your answer

const buffer = new ArrayBuffer(8);
const result =  buffer.byteLength;

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Create a byte view

javascript Your answer

const buffer = new ArrayBuffer(4);
const bytes = new Uint8Array(buffer);
const result =  bytes.length;

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Read the same storage through another view

javascript Your answer

const buffer = new ArrayBuffer(4);
const bytes = new Uint8Array(buffer);
bytes[0] = 0x34;
const words = new Uint16Array(buffer);
const result =  words[0];

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Read a view offset

javascript Your answer

const buffer = new ArrayBuffer(8);
const view = new Uint8Array(buffer, 2, 3);
const result =  view.byteOffset;

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Create clamped bytes

javascript Your answer

const values = new Uint8ClampedArray([300]);
const result =  values[0];

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Create a 64-bit BigInt view

javascript Your answer

const values = new BigInt64Array([2n]);
const result =  values[0];

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Read little-endian Uint16

javascript Your answer

const buffer = new ArrayBuffer(2);
const view = new DataView(buffer);
view.setUint16(0, 0x1234, true);
const result =  view.getUint16(0, true);

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Write a big-endian Uint32

javascript Your answer

const buffer = new ArrayBuffer(4);
const view = new DataView(buffer);
const result =  view.setUint32(0, 0x12345678, false);

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