The lastIndexOf()
method returns the last index at which a given element can be found in the typed array, or -1 if it is not present. The typed array is searched backwards, starting at fromIndex
. This method has the same algorithm as Array.prototype.lastIndexOf()
. TypedArray is one of the typed array types here.
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Syntax
typedarray.lastIndexOf(searchElement[, fromIndex = typedarray.length])
Parameters
searchElement
- Element to locate in the typed array.
fromIndex
- Optional. The index at which to start searching backwards. Defaults to the typed array's length, i.e. the whole typed array will be searched. If the index is greater than or equal to the length of the typed array, the whole typed array will be searched. If negative, it is taken as the offset from the end of the typed array. Note that even when the index is negative, the typed array is still searched from back to front. If the calculated index is less than 0, -1 is returned, i.e. the typed array will not be searched.
Return value
The last index of the element in the array; -1
if not found.
Description
lastIndexOf
compares searchElement
to elements of the typed array using strict equality (the same method used by the ===, or triple-equals, operator).
Examples
Using lastIndexOf
var 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 (ECMA-262) The definition of 'TypedArray.prototype.lastIndexOf' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
lastIndexOf | Chrome Full support 45 | Edge Full support 14 | Firefox
Full support
37
| IE No support No | Opera Full support 32 | Safari Full support 10 | WebView Android Full support 45 | Chrome Android Full support 45 | Firefox Android
Full support
37
| Opera Android Full support 32 | Safari iOS Full support 10 | Samsung Internet Android Full support 5.0 | nodejs Full support 4.0.0 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.
- See implementation notes.