how to properly use dayjs inside vue 3 app and component

Question

I am able to use dayjs inside vue3 component by adding it to data()

import dayjs from 'dayjs'

export default {
  data() {
    return {
      dayjs
    }
  }
}

Then I will be able to use it inside template but is this the correct way to do?

What if I want to configure dayjs and use it globally? I tried

import dayjs from 'dayjs'
import { createApp } from 'vue'
const app = createApp(App)
    
app.use(dayjs) // doesn't work
app.dayjs = dayjs // doesn't work
    
app.mount("#app')

but couldn't get it to work so far.
What is the correct way to do it?

Answer 1

u can use

import dayjs from 'dayjs'
import { createApp } from 'vue'
const app  = createApp(App)
    
app.config.globalProperties.$dayjs = dayjs
    
app.mount("#app')

Answer 2

The accepted method does not seem to take into account composition API. My understanding is that the only way to use this with Composition API is to provide/inject. Example below working with composition API, options API in script and templates.

//[main.js]

import dayjs from 'dayjs' //import dayjs in your main.js
 
app.provide('dayJS', dayjs) // provide dayJS

app.use(router).mount("#app") // mount app

// [component.js]

// Composition API setup ------------------
import { inject } from 'vue' // import inject from vue
const dayJS = inject("dayJS") // inject dayJS

//make sure that you return dayJS in setup along with any functions/variables
return { dayJS }

// Options API setup ------------------
app.component('mycomponent', {
  inject: ['dayJS'],
  created() {
    console.log(dayJS())  
  }
})

//You can now use dayJS directly within setup ex: dayJS() or template ex: {{dayJS()}}.

Answer 3

You can use provide/inject to use dayjs inside of your component.

//main.js
import dayjs from 'dayjs'
import { createApp } from 'vue'

const app = createApp({
  provide() {
    return {
      $dayjs: dayjs // <-- provide 
    }
  },    
    
app.mount("#app')

//myComponent.vue
<template>
    DajsJS: {{ myDays }}
</template>

<script>
export default {
  name: 'myComponent',
  inject: ['$dayjs'], // <-- inject
  computed: {
    myDays() {
      return this.$dayjs('1990-01-01')
    }
  }
}
</script>