04. BASICS | Strings in JavaScript

let name = 'Shubham'; // string created using single quote

let name = "Shubham"; // string created using double quote

Strings are immutable. We can't modify the string at the same memory address. The modified string will be created at the new memory address.

In order to access the character at an index, we use the following syntax:-

let name = 'shubham';
name[0] // s
name[1] // h

let name = new String('amit');

typeof(name) // Object, not string anymore

/*
0: "a"
1: "m"
2: "i"
3: "t"
*/

Template Literal

Template literal uses backticks instead of quotes to define a string.

let name = `Shubham`; // string created using backticks

With template literal, it is possible to use both single as well as double quotes inside a string.

let sentence = `This is Shubham's book. Title is "JavaScript".`;

We can insert variables directly in template literal. This is called string interpolation.

let name = 'Shubham';

let sentence = `My name is ${name}.`; // Output: My name is Shubham.

Escape Characters

In JavaScript, the backslash (\) is used as the escape character to include special characters in a string that would otherwise be difficult to type or cause syntax errors. The backslash signals to the JavaScript compiler to treat the character(s) that follow it differently.

let text= 'It\'s alright.';
// Output: It's alright.

let text = "We are the so-called \"Vikings\" from the north.";
// Output: We are the so-called "Vikings" from the north.

let text = "The character \\ is called backslash.";
// Output: The character \ is called backslash.

String Properties and Methods

let name = 'Shubham';
name.length // Output: 5


/**NOTE:- 
 * All the below methods will return the new string.
 * Original string(s) will remain unchanged.
**/
let name = 'Shubham';
name.toUpperCase() // Output: SHUBHAM

let name = 'Shubham';
name.toLowerCase() // Output: shubham

let name = 'Shubham';
name.slice(2, 4) // Output: ub (index 4 not included!)

let name = 'Shubham';
name.slice(2) // Output: ubham

let name = 'Shubham Bhai';
name.replace('Bhai', 'Bhau') // Output: Shubham Bhau

let name1 = 'Shubham';
let name2 = 'Agrawal';
name.concat(name2, "25") // Output: Shubham25Agrawal

let name = ' Shubham    ';
name.trim() // Output: Shubham

Happy reading!