Vue 忽略数据重复

Question

我是 Vue 的新手，正在尝试从我的数组对象中删除数据重复。

VIEW

<div id="app">
  <h2>Programming Classes Time</h2>
  <div v-for="todo in todos">
    <p>{{todo.time}}</p>

/** Is there a way to display 7:00 PM only once and under 7:00 PM display Javascript, JQuery and PHP **/
/** display 8:00 PM only once and under it there should be CSS, HTML and MySQL **/

    <p>{{todo.text}}</p>
    <br/>
  </div>
</div>

脚本

new Vue({
  el: "#app",
  data: {
    todos: [
      { text: "Javascript", time: "7:00 PM" },
      { text: "JQuery", time: "7:00 PM" },
      { text: "PHP", time: "7:00 PM" },
      { text: "CSS", time: "8:00 PM" },
      { text: "HTML", time: "8:00 PM" },
      { text: "MySQL", time: "8:00 PM" }
    ]
  },
  methods: {
    toggle: function(todo){
        todo.done = !todo.done
    }
  }
})

有没有办法让7:00 PM只显示一次，然后在下面显示Javascript、JQuery和PHP如下图？

下面是我在 jsfiddle

上的代码

https://jsfiddle.net/ujjumaki/hu9ytvwn/14/

Answer 1

创建一个计算属性来对您的数据进行分组。例如

computed: {
  todosByTime () {
    const grouped = this.todos.reduce((map, { text, time }) => {
      let group = map.get(time) || map.set(time, []).get(time)
      group.push(text)
      return map
    }, new Map())

    return Array.from(grouped, ([ time, texts ]) => ({ time, texts }))
  }
}

现在您可以在模板中使用它了

<dl>
  <template v-for="todo in todosByTime" :key="todo.time">
    <dt>{{ todo.time }}</dt>
    <dd v-for="text in todo.texts">{{ text }}</dd>
  </template>
</dl>

Answer 2

你可以试试：

new Vue({
  el: "#app",
  data: {
    todos: [
      { text: "Javascript", time: "7:00 PM" },
      { text: "Java", time: "8:00 PM" },
      { text: "JQuery", time: "7:00 PM" },
      { text: "PHP", time: "7:00 PM" },
      { text: "CSS", time: "8:00 PM" },
      { text: "HTML", time: "8:00 PM" },
      { text: "Python", time: "7:00 PM" },
      { text: "MySQL", time: "8:00 PM" },
    ],
    resolvedTodos: {}
  },
  mounted() {
    this.resolvedTodos = this.todos.reduce((acc, item) => {
      acc[item.time] = 
        !Object.keys(acc).find(a => a === item.time) 
          ? [item.text] 
          : [...acc[item.time], item.text]
      return acc
    }, {})
  },
  methods: {
    toggle: function (todo) {
      todo.done = !todo.done;
    },
  },
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.11/vue.min.js"></script>
<div id="app">
  <h2>Programming Classes Time</h2>
  <div v-for="(langs, time in resolvedTodos">
    {{ time }}
    <div v-for="lang in langs">
      {{ lang }}
    </div>
    <br />
  </div>
</div>

Vue 忽略数据重复

Vue ignore data repetition

vue.js

datarepeater