Strings Tutorial | DevBrainBox

Strings

Work with text and common string operations.

Strings are one of the most commonly used data types in JavaScript. A string is a sequence of characters used to represent text. Names, messages, email addresses, product descriptions, and page content are all examples of strings.

What Is a String?

A string is text enclosed within single quotes, double quotes, or backticks.

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let name = "John";
let city = 'Delhi';
let message = `Welcome to JavaScript`;

Creating and Displaying Strings

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let greeting = "Hello World";

console.log(greeting);

Output:

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Hello World

String Length

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let language = "JavaScript";

console.log(language.length);

Output:

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Converting Text Case

toUpperCase()

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let name = "john";

console.log(name.toUpperCase());

Output:

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JOHN

toLowerCase()

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let email = "USER@EMAIL.COM";

console.log(email.toLowerCase());

Output:

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user@email.com

Finding Text in a String

includes()

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let message = "Welcome to JavaScript";

console.log(message.includes("JavaScript"));

Output:

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true

indexOf()

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let text = "Hello World";

console.log(text.indexOf("World"));

Output:

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Replacing Text

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let message = "Hello John";

let updatedMessage = message.replace("John", "Sarah");

console.log(updatedMessage);

Output:

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Hello Sarah

Extracting Part of a String

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let text = "JavaScript";

console.log(text.slice(0, 4));

Output:

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Java

Template Literals

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let name = "John";

let message = `Hello, ${name}!`;

console.log(message);

Output:

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Hello, John!

Real-World Example

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let username = "john";

console.log(username.toUpperCase());

Output:

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JOHN

Summary

Strings store and manage text in JavaScript. Methods such as length, toUpperCase(), toLowerCase(), includes(), replace(), and slice() make it easy to manipulate text in real web applications.