The JavaScript Array lastIndexOf() Method is used to find the index of the last occurrence of the search element provided as the argument to the function.
Syntax:
array.lastIndexOf(element, start)
Parameters: This method accepts two parameters as mentioned above and described below:
- element: This parameter holds the element whose index will be returned.
- start: This parameter is optional and it holds the starting point of the array, where to begin the search the default value is 0.
Return value: This method returns the index of the last occurrence of the element. If the element cannot be found in the array, then this method returns -1.
Below is an example of the Array lastIndexOf() method.
Example:
javascript
let name = ['gfg', 'cse', 'neveropen', 'portal'];a = name.lastIndexOf('gfg')// Printing result of methodconsole.log(a); |
Output:
0
Example 1: In this example, the method will be searched for element 2 in that array and return that element index.
javascript
// Taking input as an array A// having some elements.let A = [1, 2, 3, 4, 5];// lastIndexOf() method is called to// test whether the searching element// is present in given array or not.a = A.lastIndexOf(2)// Printing result of method.console.log(a); |
Output:
1
Example 2: In this example, the method will search for the element 9 in that array if not found then return -1.
javascript
// Taking input as an array A// having some elements.let name = ['gfg', 'cse', 'neveropen', 'portal'];// lastIndexOf() method is called to// test whether the searching element// is present in given array or not.a = name.lastIndexOf('cat')// Printing result of methodconsole.log(a); |
Output:
-1
We have a complete list of Javascript Array methods, to check those please go through this Javascript Array Complete reference article.
Supported Browsers: The browsers supported by JavaScript Array lastIndexOf() method are listed below:
- Google Chrome 38 and above
- Microsoft Edge 12 and above
- Mozilla Firefox 28 and above
- Safari 8 and above
- Opera 25 and above
We have a Cheat Sheet on Javascript where we covered all the important topics of Javascript to check those please go through Javascript Cheat Sheet-A Basic guide to JavaScript.
