check first 2 characters string javascript code example

Example 1: javascript get first 2 char

String.substring(0, 2);
//Return the first two characters of the string
//First parameter is the starting index, 0 corresponding to the first character
//Second parameter is the number of character to return

Example 2: substring javascript

var str = "Hello world!";
var res = str.substring(1, 4); //ell

Example 3: str.substring if 2 letters

public String firstTwo(String str) {
    return str.length() < 2 ? str : str.substring(0, 2);
}