1. String slice() Method
To get the first N characters of a string in JavaScript, call the slice() method on the string, passing 0 as the first argument and N as the second. For example, str.slice(0, 2) returns a new string containing the first 2 characters of str.
const str = 'Coding Beauty';
const first2 = str.slice(0, 2);
console.log(first2); // Co
const first6 = str.slice(0, 6);
console.log(first6); // Coding
const first8 = str.slice(0, 8);
console.log(first8); // Coding B
The String slice() method extracts the part of a string between the start and end indexes, which are specified by the first and second arguments respectively. The substring between the indexes 0 and N is a substring containing only the first N string characters.
Note
Strings in JavaScript are immutable, and the slice() method returns a new string without modifying the original:
const str = 'Coding Beauty';
const first2 = str.slice(0, 2);
console.log(first2); // Co
// Original not modified
console.log(str); // Coding Beauty
2. String substring() Method
To get the first N characters of a string, we can also call the substring() method on the string, passing 0 and N as the first and second arguments respectively. For example, str.substring(0, 3) returns a new string containing the first 3 characters of str.
const str = 'Coding Beauty';
const first3 = str.substring(0, 3);
console.log(first3); // Cod
const first5 = str.substring(0, 5);
console.log(first5); // Codin
const first11 = str.substring(0, 11);
console.log(first11); // Coding Beau
Like slice(), substring() returns the part of a string between the start and end indexes, which are specified by the first and second arguments respectively.
Note
substring() returns a new string without modifying the original:
const str = 'Coding Beauty';
const first3 = str.substring(0, 3);
console.log(first3); // Cod
// Original not modified
console.log(str); // Coding Beauty
Tip
The slice() and substring() methods work similarly for our scenario, but this isn’t always the case. Here’s one difference between them: substring() swaps its arguments if the first is greater than the second, but slice() returns an empty string (''):
const str = 'Coding Beauty';
const substr1 = str.substring(2, 0);
const substr2 = str.slice(2, 0);
// Equivalent to str.substring(0, 2)
console.log(substr1); // Co
console.log(substr2); // '' (empty string)11 Amazing New JavaScript Features in ES13
This guide will bring you up to speed with all the latest features added in ECMAScript 13. These powerful new features will modernize your JavaScript with shorter and more expressive code.
Simple and fast, thank you.