JavaScript TypedArray lastIndexOf() Method

The JavaScript lastIndexOf method returns the final index of a specified value within a string or an array. If the value does not exist, it will yield -1.

NOTE: The string is searched from the end to the beginning, but returns the index starting from the beginning, at position 0.

The lastIndexof method is case sensitive.

Syntax:

array.lastIndexOf(value, start)

Parameters:

Value: The initial parameter represents the value that will be sought within the array.

Start: This denotes the location from which the search will commence. In the absence of a specified value in the argument, the default setting is the length of the array.

Return value:

Indicating the position of the element where the specified value appears for the final time, or returning -1 if the value is not present.

Browser Support:

Example

JavaScript lastIndexOf Method

<script type="text/javascript">

 // JavaScript to illustrate lastIndexOf() method

function pyVisualizer() {

    // string

    var str = 'Example'; 

    //Finding the index of the string

    var index = str.lastIndexOf('T');

    document.write(index);

}

runExample();

// expected output: arr[Output:4]

</script>

Output:

Example 2

JavaScript lastIndexOf Method

<script type="text/javascript">

 // JavaScript to illustrate lastIndexOf() method

function pyVisualizer() {

// string

 var str = 'Example';

 //Finding the index of the string

 var index = str.lastIndexOf('s');

 document.write(index);

}

runExample();

// expected output: arr[Output:-1]

</script>

Output: