TypedArray.prototype.lastIndexOf() - JavaScript | MDN
Try it
const uint8 = new Uint8Array([10, 20, 50, 50, 50, 60]);
console.log(uint8.lastIndexOf(50, 5));
// Expected output: 4
console.log(uint8.lastIndexOf(50, 3));
// Expected output: 3
Syntax
js
lastIndexOf(searchElement)
lastIndexOf(searchElement, fromIndex)
Parameters
searchElement-
Element to locate in the typed array.
fromIndexOptional-
Zero-based index at which to start searching backwards, converted to an integer.
Return value
The last index of searchElement in the typed array; -1 if not found.
Description
See Array.prototype.lastIndexOf() for more details. This method is not generic and can only be called on typed array instances.
Examples
Using lastIndexOf()
js
const uint8 = new Uint8Array([2, 5, 9, 2]);
uint8.lastIndexOf(2); // 3
uint8.lastIndexOf(7); // -1
uint8.lastIndexOf(2, 3); // 3
uint8.lastIndexOf(2, 2); // 0
uint8.lastIndexOf(2, -2); // 0
uint8.lastIndexOf(2, -1); // 3
Specifications
| Specification |
|---|
| ECMAScript® 2027 Language Specification # sec-%typedarray%.prototype.lastindexof |