Getting Started With Vue CLI 3 + TypeScript

Creating a project

Note that the following steps can also be achieved on the Vue GUI — to open it type Vue ui into your command line.

Start off by creating a Vue CLI project as normal:

# Install Vue CLI if it isn't already installed
npm install --global @vue/cli

# Create a new project
vue create my-project-name

When prompted, choose ‘Manually select features’ and then select TypeScript. Select any other features that you would like.

Further options

After this, you’ll be asked to select additional options.

Use class-style component syntax? Vue TypeScript components can be written in either of two ways:

• Basic usage, with Vue.extend()
• Class-style, with @Component decorator

Answer Yes to install the libraries needed to write class-style components.

Pick a linter / formatter config: 

Choose TSLint for appropriate TypeScript syntax checking and analysis.

Wait for the project to be created, and then type npm run serve to see it live.

Project structure

Your folder structure will look similar to a typical Vue CLI project. Some files are specific to TypeScript projects:

Project:
|   babel.config.js
|   package-lock.json
|   package.json
|   postcss.config.js
|   README.md
|   tsconfig.json
|   tslint.json
|   .browserslistrc
|   .gitignore
|   
+---node_modules 
|
+---public
|   |   favicon.ico
|   |   index.html
|   |   manifest.json
|   |   robots.txt
|   |   
|   \---img
|       \---icons
|               
\---src
    |   App.vue
    |   main.ts
    |   registerServiceWorker.ts
    |   router.ts
    |   shims-tsx.d.ts
    |   shims-vue.d.ts
    |   store.ts
    |   
    +---assets
    |       logo.png
    |       
    +---components
    |       HelloWorld.vue
    |       
    \---views
            About.vue
            Home.vue

tsconfig.jsonDenotes a TypeScript project. Contains compiler options and specifies the location of root files.

tslint.jsonOptions and rules for Typescript linting, for TSlint.

main.ts The equivalent of main.js; the entry file for the project.

shims-tsx.d.ts Allows the use of .tsx files. Read more about this here.

shims-vue.d.ts Allows .vue single file components to be imported and used.

Writing components

We can now write TypeScript in .vue single file components, within the script tags.

<script lang="ts"></script>

Components are written using either Vue.extend() or the @Component decorator. Choose the way that is best suited to your needs.

Basic usage, with Vue.extend()

Similar to declaring a normal Vue component. Vue.extend() is used so that the code inside can be subject to type inference.

<template>
  <div>
    <h1>{{ msg }}</h1>
  </div>
</template>

<script lang="ts">
import Vue from 'vue';
export default Vue.extend({
  name: 'HelloWorld',
  props: {
    msg: String,
  },
});
</script>

<style scoped lang="scss">
</style>

Class-style, with @Component decorator

Decorators, such as @Prop, @Watch, @Emit, are used to define the component. 

This is achieved using a combination of two libraries, vue-class-component and vue-property-decorator.

<template>
  <div>
    <h1>{{ msg }}</h1>
  </div>
</template>

<script lang="ts">
import { Component, Prop, Vue } from 'vue-property-decorator';
@Component
export default class HelloWorld extends Vue {
  @Prop() private msg!: string;
}
</script>

<style scoped lang="scss">
</style>

IDE support for TypeScript

TypeScript support and features are available with these IDEs:

• Basic usage, with Vue.extend()
• Class-style, with @Component decorator

#vue-js #typescript #javascript #web-development