var ext = fileName.split(‘.’).pop();

var fileName = “myDocument.pdf”;<br /> var fileExtension = fileName.split(‘.’).pop(); //”pdf”

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

let filename = “index.js”;<br /> let extension = filename.split(“.”).pop();</p> <p>console.log(extension); // “js”

// Use the lastIndexOf method to find the last period in the string, and get the part of the string after that:</p> <p>var ext = fileName.substr(fileName.lastIndexOf(‘.’) + 1);<br />

var fileName = “myDocument.pdf”;<br /> var fileExtension = fileName.split(‘.’).pop(); //”pdf”

file.originalname.match(/\..*$/)[0]