DataView.prototype.setBigInt64()

The setBigInt64() method of DataView instances takes a BigInt and stores it as a 64-bit signed integer in the 8 bytes starting at the specified byte offset of this DataView. There is no alignment constraint; multi-byte values may be stored at any offset within bounds.

// Create an ArrayBuffer with a size in bytes
const buffer = new ArrayBuffer(16);

// Highest possible BigInt value that fits in a signed 64-bit integer
const max = 2n ** (64n - 1n) - 1n;

const view = new DataView(buffer);
view.setBigInt64(1, max);

console.log(view.getBigInt64(1));
// Expected output: 9223372036854775807n

Syntax

setBigInt64(byteOffset, value)
setBigInt64(byteOffset, value, littleEndian)

Parameters

• byteOffset
  • : The offset, in bytes, from the start of the view to store the data in.
• value
  • : The value to set as a BigInt. For how the value is encoded in bytes, see Value encoding and normalization.
• littleEndian Optional
  • : Indicates whether the data is stored in little- or big-endian format. If false or undefined, a big-endian value is written.

Return value

undefined.

Exceptions

• RangeError
  • : Thrown if the byteOffset is set such that it would store beyond the end of the view.

Examples

Using setBigInt64()

const buffer = new ArrayBuffer(10);
const dataview = new DataView(buffer);
dataview.setBigInt64(0, 3n);
dataview.getBigInt64(1); // 768n

Specifications

Browser compatibility

See also

• JavaScript typed arrays guide
• DataView
• ArrayBuffer
• BigInt64Array