b-form-selectで値が変わったときになにか処理をする

bootstrap-vue.js.org

<template>
  <div>
    <b-form-select v-model="selected" :options="options" @change="handleSelectChanged"></b-form-select>
  </div>
</template>

<script>
  export default {
    data() {
      return {
        selected: null,
        options: [
          { value: null, text: 'Please select an option' },
          { value: 'a', text: 'This is First option' },
          { value: 'b', text: 'Selected Option' }
        ]
      }
    },
    methods: {
      handleSelectChanged: () => {
        console.log("change");
      }
    }
  }
</script>