Vue 通过 Lodash 限制操作频率

<template>  <div id="watch-example">    <p>        Ask a yes/no question:        <input v-model="question">    </p>    <p>{{ answer }}</p>  </div></template><script>import _ from 'lodash'import axios from 'axios'  export default{  data(){    return {      question: '',      answer: 'I cannot give you an answer until you ask a question!'    }  },  watch: {    // 如果 `question` 发生改变,这个函数就会运行    question: function (newQuestion, oldQuestion) {      this.answer = 'Waiting for you to stop typing...'      this.debouncedGetAnswer()    }  },  created: function () {    // `_.debounce` 是一个通过 Lodash 限制操作频率的函数。    // 在这个例子中,我们希望限制访问 yesno.wtf/api 的频率    // AJAX 请求直到用户输入完毕才会发出。想要了解更多关于    // `_.debounce` 函数 (及其近亲 `_.throttle`) 的知识,    // 请参考:https://lodash.com/docs#debounce    this.debouncedGetAnswer = _.debounce(this.getAnswer, 500)  },  methods: {    getAnswer: function () {      if (this.question.indexOf('?') === -1) {        this.answer = 'Questions usually contain a question mark. ;-)'        return      }      this.answer = 'Thinking...'      var vm = this      axios.get('https://yesno.wtf/api')        .then(function (response) {          vm.answer = _.capitalize(response.data.answer)        })        .catch(function (error) {          vm.answer = 'Error! Could not reach the API. ' + error        })    }  }}</script>