get file extension from http response javascript code example

Example 1: javascript get file extension

var fileName = "myDocument.pdf";
var fileExtension = fileName.split('.').pop(); //"pdf"

Example 2: javascript get file extension from string

// Use the lastIndexOf method to find the last period in the string, and get the part of the string after that:

var ext = fileName.substr(fileName.lastIndexOf('.') + 1);