Svelte-Svelte dev help and code

Example

In Svelte, reactivity is built directly into the language. Variables are reactive by default, meaning when their values change, the UI updates automatically.

Scenario

Imagine you are building a form where a user selects an option from a dropdown menu, and depending on the option, other form fields dynamically appear. With Svelte, you simply bind the UI elements to reactive variables, and Svelte takes care of updating the DOM. Here’s an example code snippet: ```Svelte introduction and functionssvelte <script> let selectedOption = 'option1'; </script> <select bind:value={selectedOption}> <option value='option1'>Option 1</option> <option value='option2'>Option 2</option> </select> {#if selectedOption === 'option1'} <p>You selected Option 1</p> {/if} ```

Example

Svelte components are self-contained, meaning they have their own styles, logic, and templates that can be reused across the application.

Scenario

Consider a scenario where you need a reusable modal dialog component across several pages. With Svelte, you can define this modal as a component and pass dynamic content to it based on the context where it is used. The modal itself would handle all of its internal logic and styling. ```svelte // Modal.svelte <script> export let isVisible = false; export let content = ''; </script> {#if isVisible} <div class='modal'> <div class='content'>{content}</div> </div> {/if} ```

Example

Svelte eliminates the need for a virtual DOM, compiling components directly into efficient imperative code that updates the DOM as needed.

Scenario

Imagine a scenario where performance is critical, such as in an application with a large amount of real-time data like a live stock ticker or sports score tracker. Traditional frameworks like React or Vue use a virtual DOM to reconcile changes, which can be inefficient for high-performance applications. With Svelte, the compiled code updates the DOM directly, reducing overhead and improving performance. For example, a real-time stock price component could be built in Svelte where the data is automatically reflected in the UI as it changes.