Conditional Rendering in Svelte

Conditional rendering is a crucial concept in Svelte that allows you to selectively display or hide elements or components based on specific conditions. It provides a powerful way to create dynamic user interfaces and handle varying states in your Svelte applications.

if and else Statements

Svelte provides a simple and intuitive way to conditionally render elements using the if and else statements. With these statements, you can control the presence or absence of specific content based on a condition.

 {#if condition}
  <p>Rendered if the condition is true</p>
{:else}
  <p>Rendered if the condition is false</p>
{/if}

In the code example above, the content within the {#if} block will be rendered if the condition is true. If the condition is false, the content within the {:else} block will be rendered instead. This allows you to dynamically display different content based on the evaluation of a condition.

Conditional Rendering with Each Blocks

In addition to the if statement, Svelte also provides the each block for conditional rendering within loops. The each block allows you to iterate over an array or iterable object and conditionally render elements based on specific conditions.

 {#each items as item}
  {#if item.condition}
    <p>Rendered for items that meet the condition</p>
  {:else}
    <p>Rendered for items that do not meet the condition</p>
  {/if}
{/each}

In the code snippet above, the {#each} block is used to iterate over the items array. Within the block, the if statement is used to conditionally render different content based on the condition for each individual item in the array.

Assigning Variables in if Statements

Svelte allows you to assign variables within an if statement using the let keyword. This can be particularly useful when you need to reuse the evaluated result of a condition within the corresponding if block.

 {#if condition let result = value}
  <p>The condition is true, and the result is {result}</p>
{:else}
  <p>The condition is false</p>
{/if}

In the above example, the let result = value within the if statement assigns the evaluated value to the result variable. This allows you to use and reference the result variable within the {#if} block.

Conditional rendering in Svelte provides a straightforward way to control the visibility and behavior of elements or components based on specific conditions. This flexibility enables you to create dynamic and interactive user interfaces, enhancing the overall user experience of your Svelte applications.

Now that you have a solid understanding of conditional rendering in Svelte, you can start implementing this powerful feature in your own projects. Happy coding!