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javascript instance method

ArrayBuffer.prototype.resize()

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The resize() method of ArrayBuffer instances resizes the ArrayBuffer to the specified size, in bytes.

Interactive exampleOpen the canonical MDN source to run this embedded demo.
const buffer = new ArrayBuffer(8, { maxByteLength: 16 });

console.log(buffer.byteLength);
// Expected output: 8

buffer.resize(12);

console.log(buffer.byteLength);
// Expected output: 12

Syntax

resize(newLength)

Parameters

  • newLength
    • : The new length, in bytes, to resize the ArrayBuffer to.

Return value

None (undefined).

Exceptions

Description

The resize() method resizes an ArrayBuffer to the size specified by the newLength parameter, provided that the ArrayBuffer is resizable and the new size is less than or equal to the maxByteLength of the ArrayBuffer. New bytes are initialized to 0.

Note that you can use resize() to shrink as well as grow an ArrayBuffer — it is permissible for newLength to be smaller than the ArrayBuffer’s current byteLength.

Examples

Using resize()

In this example, we create a 8-byte buffer that is resizable to a max length of 16 bytes, then check its resizable property, resizing it if resizable returns true:

const buffer = new ArrayBuffer(8, { maxByteLength: 16 });

if (buffer.resizable) {
  console.log("Buffer is resizable!");
  buffer.resize(12);
}

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also