lastIndexOf() Method in JavaScript

The method in JavaScript is used to find the index of the last occurrence of a specified value in an .
It returns the index of the last matching element.
The search starts from the last index of the array but only shows the last occurrence.
It takes two arguments:
- search-element: The value to search for.
- from-index (optional): The index from which to start the search. If not provided, it searches from the end of the array.
If the element is not found, it returns .

Example:

1const names = ['john', 'max', 'alex', 'tony', 'smith', 'tony', 'jack'];

1const indexNo = names.lastIndexOf('tony');
2console.log(indexNo);
3
4
5
6// Output:
75

The search starts from the end of the array and returns because the last occurrence of is at index .

Now, if you provide a value, the search starts from that index and searches backward.

1const indexNo = names.lastIndexOf('tony', 4);
2console.log(indexNo);
3
4
5
6// Output:
7// 3

With set to , the search starts from index and finds the last occurrence of at index .

The method helps in finding the last occurrence of a value, optionally from a specified starting point.

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