Vue Options API vs Composition API Quiz Quiz

Explore the key differences and advantages of the Vue Options API and Composition API with this focused quiz. Assess your understanding of Vue's component structuring and coding approaches, including practical scenarios and common use cases.

1. Component Structure Comparison

   Which statement accurately describes a key difference between organizing logic in Vue's Options API versus the Composition API?

   1. The Composition API cannot handle component lifecycle hooks, but the Options API can.
   2. The Options API organizes component code by option type like data or methods, while the Composition API groups related logic together using functions.
   3. The Options API uses only script tags, whereas the Composition API always requires template tags.
   4. The Options API requires all code to be placed inside the mounted hook.

   Explanation: The Options API separates logic by options such as data, methods, and computed, making it harder to group related features. By contrast, the Composition API allows developers to group logic by feature using setup functions, improving code reusability. The statement about script and template tags is incorrect because both APIs can use both tags. Lifecycle hooks are available in both APIs, though called differently. Finally, the Options API does not require placing all code in the mounted hook.

2. Reactivity Handling

   How does the Composition API primarily enable reactivity within components when compared to the Options API?

   1. By automatically making all variables reactive without explicit declaration
   2. By using ref and reactive functions to declare reactive state in the setup function
   3. Only by using computed properties outside of methods
   4. Through event listeners instead of state variables

   Explanation: The Composition API relies on ref and reactive to explicitly define reactive variables in the setup function, giving developers fine-grained control over reactivity. Using only computed properties is not sufficient to declare state. Automatic reactivity of all variables is not the case; reactivity must be explicitly defined. The use of event listeners is unrelated to the core reactive model.

3. Reusability and Code Sharing

   A developer wants to reuse a piece of logic across multiple components. Which API provides a more flexible method for sharing logic, and what is the commonly used approach?

   1. Options API, by copying and pasting methods between components
   2. Options API, using global data properties
   3. Composition API, using data mixins only
   4. Composition API, using composable functions

   Explanation: The Composition API encourages extracting reusable logic into composable functions, which can be shared among components easily. While the Options API can use mixins, composable functions are generally more flexible and avoid issues with mixin property name conflicts. Global data properties are not a typical pattern for sharing logic. Simply copying methods leads to duplication rather than true reusability.

4. Lifecycle Hook Usage

   Which is the correct way to access a component's mounted lifecycle logic when using the Composition API?

   1. Use the mounted property directly in the template section
   2. Trigger the mounted event from the script setup block
   3. Declare a mounted method outside of setup
   4. Call the onMounted function inside the setup function

   Explanation: With the Composition API, lifecycle hooks such as onMounted are called as functions inside the setup function, allowing for clean and explicit logic organization. The template section is only for markup, not logic. Declaring a mounted method outside setup won't connect it to the component's lifecycle. Triggering a mounted event manually is unnecessary and not a standard practice.

5. Migration Considerations

   When updating an existing application from the Options API to the Composition API, which of the following is a common challenge developers might face?

   1. Forgetting to install an external package for basic state management
   2. Needing to remove all template syntax from components
   3. Finding that the Composition API lacks reactivity features
   4. Understanding how to restructure logic to improve code organization and avoid duplication

   Explanation: Transitioning to the Composition API often requires reorganizing logic into composable functions, promoting better code sharing and reducing duplication, which can be challenging. The Composition API actually adds more flexible reactivity, so lacking features is incorrect. The template syntax remains unchanged. The Composition API's basic features do not require extra packages for state management.