Working with Strings in TypeScript: A Complete Guide

Updated: January 7, 2024 By: Guest Contributor Post a comment

Welcome, esteemed programmer, to this bountiful resource on the fine art of manipulating characters woven together in the TypeScript tapestry. Like the Mississippi River carves its way through the landscape, let us navigate through the flowing currents of strings and their myriad mysteries in TypeScript.


In the hearty world of TypeScript, strings are as vital as a sturdy raft to a riverboat captain, allowing data to be conveyed with clarity and precision. This guide sets sail exploring the use of strings, drawing from the wells of both basic and advanced techniques.

Basic String Operations

Our journey begins with the simplest of tools, crafting messages and sifting through alphabets. Here’s a glimpse at the fundamentals:

let greeting: string = 'Hello, world!';
console.log(greeting);  // Output: 'Hello, world!'

Being mindful not to dilly-dally, you can append two strings with a nimble ‘+’:

let firstName: string = 'Mark';
let lastName: string = 'Twain';
let fullName: string = firstName + ' ' + lastName;
console.log(fullName);  // Output: 'Mark Twain'

Templating and Interpolation

Templating strings is like painting a picture with words, where `${}` is your brush:

let age: number = 34;
let interpolation: string = `I am ${age} years old.`;
console.log(interpolation);  // I am 34 years old.

This powerful feature allows for embedding expressions within your strings, similar to an eloquent simile drawing two ideas together in literary prose.

Advanced String Functions

As we venture deeper, we encounter the ‘includes()’ function:

let passage: string = 'The quick brown fox jumps over the lazy dog';
let wordToFind: string = 'fox';
let doesInclude: boolean = passage.includes(wordToFind);
console.log(doesInclude);  // true

This function is adept at scouting a substring within the main string, much like finding a needle in a haystack.

String Comparisons

Comparing strings is akin to weighing a frog at a county fair, where precision is key:

let stringOne: string = 'Tom';
let stringTwo: string = 'Sawyer';
console.log(stringOne < stringTwo);  // true

TypeScript leads us judiciously, considering character Unicode values for such comparisons.

Regular Expressions

When one desires to extract even the most confounding phrases, regular expressions are like a trusty fishing line:

let regex: RegExp = /\b\w+a\b/g;
let text: string = 'Huck finna find a way';
let matches: string[] = text.match(regex) || [];
console.log(matches);  // [ 'finna']

Here, the pattern telegraphs its intent, snagging words that end with ‘a’.

Manipulating Character Case

To show respect or to whisper softly in a script, one might adjust the casing:

let humbleString: string = 'tom sawyer';
let loudString: string = 'TOM SAWYER';
console.log(humbleString.toUpperCase());  // 'TOM SAWYER'
console.log(loudString.toLowerCase());  // 'tom sawyer'

Such transformations are as simple as changing one’s hat from a beaver fur stovepipe to a modest derby.

String Slicing and Splicing

To extract a passage or insert a phrase, slicing and splicing are your pocketknives:

let novel: string = 'The Adventures of Tom Sawyer';
let excerpt: string = novel.slice(4, 14);
console.log(excerpt);  // 'Adventures'

Furthermore, the art of splicing is a treasure hidden within the TypeScript island, waiting to be unfurled in your hands.


In the fashion of tales end, let it be known that TypeScript masters the realm of strings as a riverboat captain tames the waters. This guide merely unlocks a chest, overflowing with tools and potential; may your journey churn the mighty river of code with ease and bring fortune to all endeavors with your newfound string proficiency.

And with this, dear reader, I bid thee a cordial farewell, as our vessel to the heartland of programming insights docks gently at the wharf.