JavaScript lastIndexOf()
Method
Example
Find the last occurrence of the string "tutorialpro":
var str = "I am from tutorialpro, welcome to tutorialpro site.";
var n = str.lastIndexOf("tutorialpro");
n Output:
28
Definition and Usage
The lastIndexOf()
method returns the position of the last occurrence of a specified string value. If a second parameter start
is specified, it searches backward from the specified position in the string.
Note: This method searches backward for the string but returns the position calculated from the start (0). It checks if the string contains the specified value.
The search starts at the specified position start
or at the end of the string (if start
is not specified).
If no matching string is found, it returns -1.
Note: The lastIndexOf()
method is case-sensitive!
Tip: You can also refer to the similar method indexOf().
Browser Support
All major browsers support the lastIndexOf()
method.
Syntax
Parameter Values
Parameter | Description |
---|---|
searchvalue | Required. The string value to search for. |
start | Optional integer parameter. Specifies the position in the string to start the search from. Its valid range is from 0 to stringObject.length - 1. If omitted, the search starts from the last character of the string. |
Return Value
Type | Description |
---|---|
Number | The position of the last occurrence of the searched string, or -1 if no match is found. |
Technical Details
| JavaScript Version: | 1.0 | | --- | --- |
More Examples
Example
Find the last occurrence of the string "tutorialpro" starting from the 20th character:
var str = "I am from tutorialpro, welcome to tutorialpro site.";
var n = str.lastIndexOf("tutorialpro", 20);
n Output:
10
Example
Find the last occurrence of the string "tutorialpro" starting from the 10th character backward:
var str = "I am from tutorialpro, welcome to tutorialpro site.";
var n = str.lastIndexOf("tutorialpro", 9);
n Output:
-1