vue3的几种书写格式

1:

<template>
  <div>

  </div>
</template>

<script >
import { defineComponent } from 'vue'

export default defineComponent({
  setup () {
    

    return {}
  }
})
</script>

<style scoped>

</style>

2：

<template>
  <div>

  </div>
</template>

<script>
import { reactive, toRefs } from 'vue'

export default {
  setup () { 
    return {
      
    }
  }
}
</script>

<style lang="scss" scoped>

</style>

3：

<template>
  <div>

  </div>
</template>

<script setup  >
 

</script>

<style scoped>

</style>