javascript substring first character code example

Example 1: how to get the first character of a string in javascript

let str = 'John Wick'
let firstChar = str.charAt(0) 
console.log(firstChar); // "J"

Example 2: reactjs cut part of string

var str = "Hello world!";

var res = str.substring(1, 4);

// res value is "ell"