VUE3 introductory tutorial: Use vue-loader to parse and compile Vue.js components

Vue.js is a popular JavaScript framework that is quite powerful in building modern web applications. Compared to traditional MVC frameworks, Vue.js provides a more semantic and intuitive way to build user interfaces. The recently released Vue 3 version introduces many new features and optimizations, making using Vue.js more accessible and flexible.

In Vue.js, components are one of the most important abstract concepts. Each component can contain its own templates, data, and methods and can be easily reused without caring about the entire state of the application. Vue.js provides a flexible component system so that developers can create highly customizable and reusable components. This article will introduce the use of vue-loader to parse and compile Vue.js components.

What is Vue-loader?

Vue-loader is a Webpack plug-in officially launched by Vue.js. It is used to parse and compile .vue files. Its main function is to convert .vue files Convert the HTML, CSS, and JavaScript code in the file into JavaScript modules so that Webpack can process these modules and bundle them into the final JavaScript file.

The main functions of Vue-loader include:

• Parse .vue files
• Support preprocessors (such as Sass and Less)
• Compile Templates, scripts and styles in .vue files

Installation of Vue-loader

To use Vue-loader, you need to install Vue.js and Webpack first. You can install these dependencies in the command line using npm:

npm install vue webpack webpack-cli vue-loader vue-template-compiler -D

After the installation is complete, you need to load the Vue-loader plugin in the Webpack configuration file. Open the webpack.config.js file and add the following code:

const VueLoaderPlugin = require('vue-loader/lib/plugin')

module.exports = {
  // ...
  module: {
    rules: [
      {
        test: /.vue$/,
        use: 'vue-loader'
      }
    ]
  },
  plugins: [
    new VueLoaderPlugin()
    // make sure to include the plugin!
  ]
}

Now, when Webpack builds your application, Vue-loader will automatically parse and compile all .vue files.

How Vue components are written

Vue components are the basic building blocks for building applications with Vue.js. As mentioned above, Vue-loader parses all .vue files into JavaScript modules. Therefore, you need to use a specific syntax to write Vue components. In this article, we will use Single File Component (SFC) syntax to write Vue components.

SFC is a syntax that packages all templates, scripts and styles into a single .vue file. Each SFC file contains the following content:

<template>
  <!-- HTML模板 -->
</template>

<script>
export default {
  // Vue组件选项
}
</script>

<style>
/* 样式 */
</style>

In the above code snippet, you can see the three important parts of the component: