Check if string begins with something? [duplicate]

Question

I know that I can do like ^= to see if an id starts with something, and I tried using that for this, but it didn't work. Basically, I'm retrieving a URL and I want to set a class for an element for path names that start in a certain way.

Example:

var pathname = window.location.pathname;  //gives me /sub/1/train/yonks/459087 

I want to make sure that for every path that starts with /sub/1, I can set a class for an element:

if (pathname ^= '/sub/1') {  //this didn't work...          ...  

Answer 1

Use stringObject.substring

if (pathname.substring(0, 6) == "/sub/1") {     // ... } 

Answer 2

String.prototype.startsWith = function(needle) {     return this.indexOf(needle) === 0; };