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BufferConstructor.from - buffer - Node documentation
method BufferConstructor.from

Usage in Deno

import { type BufferConstructor } from "node:buffer";
BufferConstructor.from(
arrayBuffer: WithImplicitCoercion<ArrayBuffer | SharedArrayBuffer>,
byteOffset?: number,
length?: number,
): Buffer

Allocates a new Buffer using an array of bytes in the range 0255. Array entries outside that range will be truncated to fit into it.

import { Buffer } from 'node:buffer';

// Creates a new Buffer containing the UTF-8 bytes of the string 'buffer'.
const buf = Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);

If array is an Array-like object (that is, one with a length property of type number), it is treated as if it is an array, unless it is a Buffer or a Uint8Array. This means all other TypedArray variants get treated as an Array. To create a Buffer from the bytes backing a TypedArray, use Buffer.copyBytesFrom().

A TypeError will be thrown if array is not an Array or another type appropriate for Buffer.from() variants.

Buffer.from(array) and Buffer.from(string) may also use the internal Buffer pool like Buffer.allocUnsafe() does.

Parameters

arrayBuffer: WithImplicitCoercion<ArrayBuffer | SharedArrayBuffer>
optional
byteOffset: number
optional
length: number

Return Type

BufferConstructor.from(data: Uint8Array | readonly number[]): Buffer

Creates a new Buffer using the passed {data}

Parameters

data: Uint8Array | readonly number[]

data to create a new Buffer

Return Type

BufferConstructor.from(data: WithImplicitCoercion<
Uint8Array
| readonly number[]
| string
>
): Buffer

Parameters

data: WithImplicitCoercion<
Uint8Array
| readonly number[]
| string
>

Return Type

BufferConstructor.from(
str: WithImplicitCoercion<string> | { [[Symbol.toPrimitive]](hint: "string"): string; },
encoding?: BufferEncoding,
): Buffer

Creates a new Buffer containing the given JavaScript string {str}. If provided, the {encoding} parameter identifies the character encoding. If not provided, {encoding} defaults to 'utf8'.

Parameters

str: WithImplicitCoercion<string> | { [[Symbol.toPrimitive]](hint: "string"): string; }
optional
encoding: BufferEncoding

Return Type