While practicing React I wanted to take it further by showing complete post only if the post id == 2.
I wanted to do with substring but didn't work, then I added toString() but still not working.
<p> {postId == 2 ? post.body : post.body.toString().substring(2, 3) } </p>
Here is a complete example, just uncomment the commented line https://codesandbox.io/s/useeffect-practice-fetch-gskpf?file=/src/index.js
Before getting data from fetchPost and call setPost your post is empty object ==> post.body is undefined. Add question mark to check if it existing do the work
// add question mark after post and body
<p> {postId == 2 ? post.body : post?.body?.toString().substring(2, 3) } </p>
Normal version
<p> {postId == 2 ? post.body : post.body ? post?.body?.toString().substring(2, 3) : 'loading...' } </p>
Try this one.... Hope it helps!!!!
let someword = "Hello there!";
console.log(someword.substring(0, 4));