Why use backtick with ${ in const in TypeScript

Issue

I am going through the angular tutorial and I see the below:

https://angular.io/tutorial/toh-pt6

const url = `${this.heroesUrl}/${hero.id}`;

Can someone explain why I need to use ` before ${ ? Since this is TypeScript and similar to JavaScript can I not use

this.heroesUrl + "/" + hero.id 

Why do I need to use backtick and the ${ operation?

Solution

That is called Template literals and it's a javascript feature, it is not typescript specific.

True, you can indeed replace this:

const url = `${this.heroesUrl}/${hero.id}`;

With:

const url = this.heroesUrl + "/" + hero.id;

But it is sometimes more comfortable to use the template literals, especially when the string is made out of a lot of parts. i.e.:

const url1 = protocol + "://" + host + ":" + port + "/" + path + "." + extension;
const url2 = `${protocol}://${host}:${port}/${path}.${extension}`;

Answered By - Nitzan Tomer