Combination function in Vue3: logically structuring components

Vue3 is an important front-end framework that provides many useful features and functions, one of which is components. Vue components are an abstract concept commonly used in front-end development. They divide the front-end page into separate, reusable parts. These parts have independent state and behavior and can be reused in different applications.

However, in practice, due to the complexity of the front-end page and the interaction between different components, the components can become cluttered and difficult to maintain. Therefore, Vue3 provides a new feature called composition function, which can effectively structure the component logic, thereby improving the readability and maintainability of the code. The following is some introduction to Vue3 composition functions.

What is a combination function?

Composition function is a new function used in Vue3, which allows developers to split the logical functions of components into multiple reusable functions and combine them together.

In Vue2, component logic is implemented through options, such as methods, computed, watcher, etc. However, this approach can lead to cluttered code structure, since all relevant options must be placed in the same object.

Vue3 changes this by combining functions. It allows us to organize component logic in a more fine-grained way, splitting functionality into smaller, independent functions. Each combination function only focuses on a certain aspect of logic, such as network requests, status updates, or event processing. They can be combined together via composition functions to achieve more complex functionality.

Advantages of combination functions

The main advantages of using combination functions are:

1. Improve code reusability

The combination function splits the component logic into Small blocks so that these small blocks can be reused in different places. For example, we can extract a function that gets data and call it multiple times in the component without having to write the method repeatedly for each component.

2. Improve code readability

Using combined functions can make the code structure clearer and easier to understand. Each function only focuses on a specific aspect of logic, which makes the code more focused and easier to maintain.

3. Independence

Combined functions have better independence. Each function only focuses on a specific aspect of logic, so that the function of each function will be simpler and clearer, and easier to test and maintain.

Practical Application

Let us use a specific example to understand how to use the combination function in Vue3.

Suppose we have a search component that needs to be used in multiple locations. The component has the following logic:

1. Receives a search term as a parameter.
2. Search for corresponding data by calling API.
3. Display the search results on the interface.

For this component, we can create a combined function named useSearch, which contains the above three logics:

import { ref } from 'vue'

export default function useSearch(keyword) {
  const searchResult = ref([])

  // 调用搜索API，并更新搜索结果
  async function search() {
    const res = await fetch(`https://api/?q=${keyword}`)
    searchResult.value = await res.json()
  }

  search() // 初始化调用一次

  return {
    searchResult,
    search
  }
}

in component

<template>
  <div>
    <input type="text" v-model="keyword" @keyup.enter="doSearch" />
    <ul>
      <li v-for="(item, index) in searchResult" :key="index">{{ item }}</li>
    </ul>
  </div>
</template>

<script>
import useSearch from './useSearch'

export default {
  setup() {
    const { search, searchResult } = useSearch('default')

    const keyword = ref('')

    function doSearch() {
      search(keyword.value)
    }

    return {
      searchResult,
      keyword,
      doSearch
    }
  }
}
</script>

By The component logic is split into separate functions to create useSearch, which we can reuse anywhere we need search functionality. In the component, we reference useSearch and create a search state associated with the component, and a doSearch function, which updates the search state by calling the search() function.

Conclusion

Vue3’s combination function makes components easier to maintain and improves code readability and reusability. By splitting component logic into separate functions and combining them together, we can structure complex functionality so that each function is simpler and easier to understand.

When we need to combine multiple functions together, we use Vue3's provide and inject functions to pass them into child components. In practice, we can use Vue3's composition functions to develop more flexible and maintainable front-end applications.

The above is the detailed content of Combination function in Vue3: logically structuring components. For more information, please follow other related articles on the PHP Chinese website!