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JavaScript lastIndexOf() Method

String Object Reference JavaScript String Object

Definition and Usage

The lastIndexOf() method returns the position of the last found occurrence of a specified value in a string.

This method returns -1 if the value to search for never occurs.

Syntax

stringObject.lastIndexOf(searchvalue,fromindex)

Parameter Description
search Required. Specifies a string value to search for
fromindex Optional. Where to start the search from (from 0 and to the length of the string). The default value is 0

Tips and Notes

Note: The lastIndexOf() method is case sensitive!

Example

Example

Do different searches within a string:

<script type="text/javascript">

var str="Hello world!";
document.write(str.lastIndexOf("Hello") + "<br />");
document.write(str.lastIndexOf("WORLD") + "<br />");
document.write(str.lastIndexOf("world"));

</script>

The output of the code above will be:

0
-1
6

Try it yourself »

String Object Reference JavaScript String Object

From http://www.w3schools.com (Copyright Refsnes Data)