Question

我是vue.js的初学者。使用计算属性而不是方法的原因是什么？为什么问这个问题是因为计算的属性和方法都做同样的事情

Answer 1

Methods can get attributes and need to be called manually, computed is not. Also you no need to clone code while multiple using. Think about computed properties like a shortcut to you additional logic.

Putting too much logic in your templates can make them bloated and hard to maintain. For example:

<div id="example">
  {{ message.split('').reverse().join('') }}
</div>

The same, using computed property:

<div id="example">
  {{ reversedMessage }}
</div>

Vue code:

var vm = new Vue({
  el: '#example',
  data: {
    message: 'Hello'
  },
  computed: {
    // a computed getter
    reversedMessage: function () {
      // `this` points to the vm instance
      return this.message.split('').reverse().join('')
    }
  }
})

Difference

But main difference as i think, is caching. When you call method 5 times, you get 5 computings. On the other side a computed property is computing only once (when changing), and then return a cached value.

为什么要在vue.js中计算属性？

1 个答案: