JavaScript lastIndexOf()

Question

In C# I can do this

string ID = "ContentPlaceHolderDefault_MainSiteSectionArea_MyPagePlaceHolder_Item4_FavoritAmusementCalender_6_deleteRight_2";   
ID = ID.Substring(ID.LastIndexOf("_") + 1); 

to return the last int 2

How can I most easily do this in jQuery/JavaScript

The id is created dynamic and can for now be up to 3 digit.

Thanks in advance.

Answer 1

You were close -- just case sensitive:

ID = ID.substring(ID.lastIndexOf("_") + 1);

JS Fiddle Example

Answer 2

JavaScript also has a lastIndexOf() method, see here. You can therefore use:

var str1 = "Blah, blah, blah Calender_6_deleteRight_272";
var str2 = str1.substr (str1.lastIndexOf ("_") + 1);

This gives you 272.

Keep in mind that, if the string doesn't contain an underscore, you'll get the original string back in its entirety. That may or may not be desired in your specific case - you can check the result of the lastIndexOf() call against -1 to detect this.