Vue.js Interview Questions and Answers #
1. What is Vue.js? #
Vue.js is a progressive JavaScript framework used for building user interfaces. It focuses on the view layer and provides a flexible and efficient way to create interactive web applications.
2. How does Vue.js differ from other JavaScript frameworks like React and Angular? #
Vue.js: Emphasizes simplicity and ease of integration into existing projects. It provides a gentle learning curve and can be used for both small and large applications.
React: Focuses on building UI components using a virtual DOM and a unidirectional data flow. It’s highly modular and often used with a state management library like Redux.
Angular: Offers a complete framework with a more opinionated approach, including a full-fledged ecosystem for building complex applications.
3. What is a Vue component? #
A Vue component is a reusable, self-contained unit that encapsulates a part of the user interface. Components can be composed of HTML, JavaScript, and CSS, and they promote reusability and maintainability in Vue.js applications.
4. Explain the Vue instance. #
The Vue instance is the root of every Vue application. It’s created using the new Vue() constructor and accepts an options object with various properties, including data, methods, computed, watch, and more.
5. What is the purpose of the data object in a Vue component?
#
The data object contains the properties that define the state of a Vue component. These properties can be accessed within the template, and any changes to them trigger reactive updates in the DOM.
6. What is the Vue template syntax? #
The Vue template syntax allows you to declaratively render dynamic data in the HTML. It uses double curly braces {{}} for data interpolation and provides directives (prefixed with v-) for control flow and binding behaviors.
7. Explain Vue directives. #
Directives are special attributes with the v- prefix that provide additional functionality to HTML elements. They allow you to perform dynamic rendering, attach event listeners, manipulate the DOM, and more.
8. What is a computed property in Vue.js? #
Computed properties are functions that dynamically compute and cache values based on reactive data. They help you avoid redundant calculations and improve performance. Computed properties are defined in the computed property of a Vue component.
9. How does Vue.js handle user input and form binding? #
Vue.js provides two-way data binding using the v-model directive. It automatically syncs the input value with the associated data property, enabling real-time updates between the input and the data.
10. What are Vue watchers? #
Watchers are used to perform actions in response to changes in data properties. They are defined in the watch property of a Vue component and allow you to watch for specific data changes and trigger custom logic.
11. Explain Vue lifecycle hooks. #
Vue components have a series of lifecycle hooks that provide the opportunity to perform actions at different stages of a component’s existence. Some common hooks include created, mounted, updated, and destroyed.
12. How can you communicate between parent and child components in Vue.js? #
Props are used to pass data from parent to child components. Events can be emitted from child components using the $emit method and listened to in the parent using the v-on directive.
13. What is Vuex? #
Vuex is a state management library for Vue.js applications. It provides a centralized store to manage the state of the entire application, making it easier to manage and share data between components.
14. What is Vue Router? #
Vue Router is a routing library for Vue.js applications. It allows you to create single-page applications with multiple views and dynamic routing capabilities.
15. Explain the concept of Vue mixins. #
Mixins are reusable code blocks that can be injected into Vue components. They allow you to encapsulate and share common logic, such as methods, computed properties, and lifecycle hooks, across multiple components.
