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.