JS Get Second To Last Index Of

Question

I am trying to figure out how to get the second to last index of a character in a string.

For example, I have a string like so:

http://www.example.com/website/projects/2 

I currently get the number 2 by using

$(location).attr('href').substring($(location).attr('href').lastIndexOf('/')+1);

But what if I want to get the word projects?

Can anybody help me out with this? Thanks in advance!

Answer 1

You can use split method:

var url = $(location).attr('href').split( '/' ); console.log( url[ url.length - 1 ] ); // 2 console.log( url[ url.length - 2 ] ); // projects // etc. 

Answer 2

Without using split, and a one liner to get the 2nd last index:

var secondLastIndex = url.lastIndexOf('/', url.lastIndexOf('/')-1) 

The pattern can be used to go further:

var thirdLastIndex = url.lastIndexOf('/', (url.lastIndexOf('/', url.lastIndexOf('/')-1) -1)) 

Thanks to @Felix Kling.

A utility function:

String.prototype.nthLastIndexOf = function(searchString, n){     var url = this;     if(url === null) {         return -1;     }     if(!n || isNaN(n) || n <= 1){         return url.lastIndexOf(searchString);     }     n--;     return url.lastIndexOf(searchString, url.nthLastIndexOf(searchString, n) - 1); } 

Which can be used same as lastIndexOf:

url.nthLastIndexOf('/', 2); url.nthLastIndexOf('/', 3); url.nthLastIndexOf('/');