Text formatting in Javascript

At some point, you may need to transform/manipulate strings to output them in the way that you want/need. You can write custom methods, but I think there's something here for you. I present to you several javascript methods for text formatting!

concat()

Combines the text of two strings and returns a new string.

let string1 = 'Hello'
let string2 = 'world!'
let string3 = string1.concat(' ', string2)
console.log(string3)
// expected output: 'Hello world!'

split()

Splits a String object into an array of strings by separating the string into substrings.

let string1 = 'I!am!saying!hello!to!the!world'

string1.split('!')
// expected output:['I','am','saying','hello','to','the','world']

toLowerCase(),toUpperCase()

Return the string in all lowercase or all uppercase, respectively.

let string = "Hello World!"

let upperString = string.toUpperCase()
let lowerString = string.toLowerCase()

console.log(upperString)
// expected output: HELLO WORLD!
console.log(lowerString)
// expected output: hello world!

slice()

Extracts a section of a string and returns a new string.

let string = "Hello World!"

console.log(string.slice(0))
//expected output: Hello World!
console.log(string.slice(5))
//expected output: World!
console.log(string.slice(-1))
//expected output: !

match(), matchAll(), replace(), replaceAll(), search()

Work with regular expressions.

const paragraph = 'The quick brown fox jumps over the lazy dog. It barked.';
const regex = /[A-Z]/g;
const found = paragraph.match(regex);

console.log(found);
// expected output: Array ["T", "I"]

const p = 'The quick brown fox jumps over the lazy dog. If the dog reacted, was it really lazy?';

const regex = /dog/gi;

console.log(p.replace(regex, 'ferret'));
// expected output: "The quick brown fox jumps over the lazy ferret. If the ferret reacted, was it really lazy?"

console.log(p.replace('dog', 'monkey'));
// expected output: "The quick brown fox jumps over the lazy monkey. If the dog reacted, was it really lazy?"

trim()

Trims whitespace from the beginning and end of the string.

const greeting = '   Hello world!   ';

console.log(greeting);
// expected output: "   Hello world!   ";

console.log(greeting.trim());
// expected output: "Hello world!";

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