JavaScript Find Last Occurrence of Substring in String

Find last occurrence of character or substring in string javascript; Through this tutorial, i am going to show you how to find last occurrence of character or substring in string javascript

JavaScript Find Last Occurrence of Substring in String

You can use the javaScript String.lastIndexOf() , which is used to find the last occurrence of a character or substring in a string.

Note that:- If the substring or occurrence character does not found instring, It returns -1.

Syntax of JavaScript lastIndexOf() Method

The following syntax demonstrates the String.lastIndexOf()  method; as shown below:

string.lastIndexOf(substring, [, startIndex]);

Remember that, this js lastIndexOf() method searches for the substring backward from the startIndex. and this startIndex is an optional parameter.

Note that, if you ignore the startIndex, the search starts from the end of the given string.

This is a very important for note that, The lastIndexOf() always perform a case-sensitive search.

Example 1- To find last occurrence of character in string javascript

Now i will take first example usinglastIndexOf() method to find the last occurrence of a character or substring 'r' in the string 'programming'; as shown below:

let str = 'programming';
let index = str.lastIndexOf('r');
console.log(index);

Output:

4

Example 2 – To find last occurrence of character in string with case sensitive in javascript

I will take second example with case sensitive string; as shown below:

let str = 'JavaScript Programming language';
let substr = 's';
let index = str.lastIndexOf(substr);
console.log(index); // -1

Conclusion

In this tutorial, you have learned everything about the lastIndexOf() string method in js with various examples.

More JavaScript Tutorials

Be First to Comment

Leave a Reply

Your email address will not be published. Required fields are marked *