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JavaScript lastIndexOf() Method

Updated:  11/27/2012 11:11 AM
Author:  Shiju Mathews

Status:    Resolved.


This one is a pretty handy function in JavaScript string operations.The lastIndexOf() method returns the position of the last occurrence of a specified value in a string.

Example
Search a string for the last occurence of "planet", starting the search at position 20:


The result of n will be:6

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

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

Note: The lastIndexOf() method is case sensitive!

Browser Support
The lastIndexOf() method is supported in all major browsers.

Syntax:
string.lastIndexOf(searchvalue,start)

Parameter Values

searchvalue: Required. The string to search for.
start:(Optional). The position where to start the search. If omitted, the default value is the length of the string.
Return Value:
Type: Number
Description: The position where the specified searchvalue occurs for the last time, or -1 if it never occurs

Technical Details:

JavaScript Version:1.0