get first three letters of string javascript code example

Example 1: javascript get first 10 characters of string

var str = "Hello world That is reallly neat!";
var res = str.substring(0, 5);//get first 5 chars

Example 2: substring javascript

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

Example 3: js substring first 4 numbwe

mystring = "9862 ....... -pack size 1 - SST Unspun Label (Roll) CAT#: 9862";

mystring = mystring.substring(0, 4);

alert(mystring.trim());