Svelte Tutorial

Svelte is an open-source Javascript framework designed to build user interfaces, mainly for web applications. Its component-based architecture has a set of reusable components. In this tutorial, we will learn Svelte and its effective utility.

Why Svelte?

• Unlike React or Vue, which do most of their work in the browser, Svelte does this work during the build process when you create your application.
• Svelte updates the DOM directly, which can make things faster and simpler.
• Svelte is a component-based framework that has a list of reusable components that allow you to build your application declaratively.
• Svelte combines JavaScript, HTML, and CSS in one file, making the code easier to read and manage.
• Svelte apps usually have smaller file sizes than those made with other frameworks. This means they load faster, which helps keep users happy and engaged.

Who Can Learn Svelte?

Svelte is a beginner-friendly framework that is easy to learn, understand, and use. Those who understand javascript, html and css can easily and quickly learn it. Svelte is good choice for web applications because it comes with component-based architecture containing reusable components and allows to build application in declarative manner.

Prerequisite to Learn Svelte

• Good knowledge of HTML − Having good knowledge of Hypertext Markup Language fundamentals and understanding of the structure of the web pages.
• Solid foundation in CSS − Having good knowledge of Cascading Stylesheets fundamentals and styling of web pages.
• JavaScript Fundamentals − Familiarity with JavaScript concepts like variables, functions, and control structures.
• ES6+ − A good knowledge of ES6 features leads to create an user engaging web applications.
• Package Managers − Basic knowledge of using npm (Node Package Manager) for managing libraries and dependencies.

Svelte Example

The following is an example of a simple application that provides the sum of two numbers, created using the Svelte framework.

<script>
    let num1 = 0;
    let num2 = 0;

    // Computed property to calculate the sum
    $: sum = num1 + num2;
</script>

<main>
    <h1>Sum of Two Numbers</h1>
    <div>
        <label for="num1">Number 1:</label>
        <input type="number" id="num1" bind:value={num1} />
    </div>
    <div>
        <label for="num2">Number 2:</label>
        <input type="number" id="num2" bind:value={num2} />
    </div>
    <h2>The sum is: {sum}</h2>
</main>

<style>
    main {
        text-align: center;
        padding: 1em;
        max-width: 240px;
        margin: 0 auto;
    }

    input {
        margin: 0.5em 0;
        padding: 0.5em;
        width: 100%;
    }

    h2 {
        color: #4CAF50;
    }
</style>

Output

Advantages of Svelte

• Smaller Bundle Size: Svelte creates efficient JavaScript from components during the build process, leading to smaller file sizes than other frameworks.
• Simpler Syntax: Svelte has a simple way of writing code, making it easier for beginners to learn and use.
• No Virtual DOM: Svelte updates the DOM directly, which can improve performance and use less memory.
• Easier State Management: Svelte has built-in stores that make it easy to manage state.
• SEO Friendly: Svelte can render on the server, which helps improve search engine rankings.

Disadvantages of Svelte

• Svelte has a smaller community than frameworks like React and Angular, so it can be harder to find help and resources.
• There aren't as many libraries and tools for Svelte as there are for React, which can restrict what developers can do.

FAQs about Svelte

There are some very Frequently Asked Questions(FAQ) about Svelte, this section tries to answer them briefly.

1. What is Svelte?

Svelte is a way of writing user interface components like a navigation bar, comment section, or contact form that users see and interact with in their browsers.

2. How does Svelte differ from React and Angular?

Unlike React and Angular, which run code in the browser, Svelte compiles code beforehand, making apps smaller and faster.

3. Does Svelte support server-side rendering (SSR)?

Yes, Svelte supports SSR through SvelteKit, which can improve the initial load time and SEO of applications.

4. How is state management handled in Svelte?

Svelte has a store API for managing state, which includes writable, readable, and derived stores to handle and respond to changes in data.

5. Can I use Svelte with other libraries?

Yes, Svelte can work with non-Svelte libraries. You can create a container in Svelte and use lifecycle methods like onMount to connect with these libraries.

6. How do I handle routing in Svelte?

You can manage p in Svelte using SvelteKit's built-in router or other libraries like page.js or svelte-routing for more options.