Vue 3 Basics

In Vue 3, components are the fundamental building blocks for constructing user interfaces. Components are reusable and self-contained modules that encapsulate HTML templates, CSS styles, and JavaScript logic. By composing multiple components together, complex applications can be built efficiently.

Components in Vue 3 feature several key characteristics:

  1. Component Definition: Components can be defined using the Vue.component() function or single-file components (.vue files). Single-file components organize HTML templates, CSS styles, and JavaScript code within a single file, offering improved readability and maintainability.
  2. Component Options: Within component definitions, various options can be specified, such as data (data), computed properties (computed), methods (methods), lifecycle hooks, etc. These options define the behavior and state of the component.
  3. Component Communication: Components communicate with each other through props and events. Props allow parent components to pass data down to child components, while children receive this data via props. Events enable child components to send messages back up to their parents; parents respond by listening for these events triggered by interactions within the children.
  4. Component Lifecycle: The component lifecycle hooks in Vue 3 have evolved. Vue 3 introduces new lifecycle functions such as beforeMount, beforeUpdate, and mounted, while deprecating older ones like beforeCreate and beforeDestroy. These hook functions allow specific operations to be executed at different stages of a component's life cycle.
  5. Component Reusability: Components in Vue 3 can be easily reused. By leveraging techniques such as mixins (mixins) and inheritance, generic logic and functionality can be injected into multiple components, thereby achieving reusability and sharing across the application.
  6. Local Component Registration: In addition to global component registration, Vue 3 supports local component registration. Within single-file components, local components can be imported and registered via the import statement and the components option, making component registration more flexible and modular.
  7. Component Fragments: Vue 3 introduces the concept of fragments (fragments). Component fragments allow a component to return multiple root elements without wrapping them in an additional parent element, enhancing both flexibility and readability.

These represent some important features and functionalities regarding components within Vue 3. Through this compositional development approach, applications can be decomposed into multiple reusable components, resulting in code that is easier to maintain, scale, and test.