svelte:component for dynamic components - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is svelte:component used for in Svelte?

svelte:component lets you render a component dynamically based on a variable. Instead of hardcoding a component, you can choose which one to show at runtime.

beginner

How do you specify which component svelte:component should render?

You pass the component constructor to the this attribute, like <svelte:component this={MyComponent} />.

beginner

Can you pass props to a component rendered with svelte:component? How?

Yes! You pass props just like normal components, by adding attributes inside <svelte:component />. For example: <svelte:component this={MyComponent} name="Alice" />.

intermediate

What happens if the variable passed to this is null or undefined?

No component is rendered. This is useful to conditionally show components dynamically.

intermediate

Why use svelte:component instead of {#if} blocks for dynamic components?

svelte:component is cleaner and scales better when you have many possible components to render. It avoids long {#if} chains and keeps code simple.

How do you tell svelte:component which component to render?

A By wrapping the component inside <code>svelte:component</code> tags

B By importing the component inside <code>svelte:component</code>

C By setting the <code>this</code> attribute to the component variable

D By using <code>bind:this</code> on the component

You specify the component to render dynamically by setting the this attribute to the component variable.

What will happen if this is null in <svelte:component this={null} />?

A No component is rendered

B A default component is rendered

C An error is thrown

D The last rendered component stays visible

If this is null, no component is rendered at all.

Can you pass props to a component rendered with svelte:component?

A No, props are not supported

B Yes, by adding attributes inside <code>&lt;svelte:component /&gt;</code>

C Only if the component is imported dynamically

D Only if you use <code>bind:this</code>

You pass props by adding attributes inside the <svelte:component /> tag, just like normal components.

Which of these is a benefit of using svelte:component?

A It allows rendering components dynamically based on variables

B It automatically optimizes component size

C It replaces the need for <code>{#if}</code> blocks completely

D It compiles components to vanilla JavaScript

svelte:component lets you render components dynamically based on variables.

If you have many possible components to render dynamically, what is the best approach?

A Use <code>bind:this</code> on each component

B Use many nested <code>{#if}</code> blocks

C Render all components and hide them with CSS

D Use <code>svelte:component</code> with a variable holding the component

Using svelte:component with a variable is cleaner and easier to maintain than many {#if} blocks.

Explain how svelte:component helps in rendering components dynamically. Include how to pass props and handle cases when no component should render.

Think about choosing components like picking clothes based on weather.

Describe a scenario where using svelte:component is better than multiple {#if} blocks for showing components.

Imagine a menu with many dishes instead of just two options.