为什么多次使用相同的 vue 指令会调用所有指令的更新? [英] Why does using the same vue directive multiple times call updates on all of them?

问题描述

我创建了一个 vue 指令，我将它附加到同一页面上的多个输入元素，并且注意到当我开始输入其中一个元素时，页面中的所有元素都会触发 'update' 事件.我原以为只有一个事件，对于我更新的特定元素.

我的问题是，有没有办法阻止事件触发，或过滤事件以便我只能处理正在更改的输入?

这是我的指令和视图的代码:

Vue.directive('test', {绑定:(el) =>{console.log(el.id + "bound")},更新:(el) =>{console.log(el.id + "更新")}})新的 Vue({el: "#app",数据: {测试值1:空，testval2:空，},方法: {}})

和模板:

<input id="testinput1" v-model="testval1" v-test/><input id="testinput2" v-model="testval2" v-test/>

这是问题的 JSFiddle:https://jsfiddle.net/eywraw8t/415288/

在这个 JSFiddle 中，您可以在控制台中看到，如果您在输入字段中输入，它会触发两个输入字段的更新.

解决方案

我认为最好的方法是使用 bind.您的指令将有一个指令适用于指定了 v-test 指令的每个元素.这是解决您问题的简单方法

Vue.directive('test', {绑定:(el) =>{console.log(el.id + "bound")const 处理程序 = (e) =>{console.log('e', e.target)如果(el == e.target){console.log(el.id + "射击")}}el.vueTest = 处理程序//添加事件监听器document.addEventListener('input', handler)},解除绑定(el，绑定){//移除事件监听器document.removeEventListener('input', el.vueTest);el.vueTest = null;}})

希望对你有帮助:)

I've created a vue directive that I'm attaching to multiple input elements on the same page, and have noticed that when I start typing in one of them, the 'update' event fires for all elements in the page. I had expected to only have one event, for the particular element that I had updated.

My question is, Is there a way to prevent the event firing, or filtering the events so that I can handle only the input that is changing?

Heres the code for my directive and view:

Vue.directive('test', {
  bind: (el) => {
    console.log(el.id + " bound")
  },
  update: (el) => {
    console.log(el.id + " updated")
  }
})

new Vue({
  el: "#app",
  data: {
    testval1: null,
    testval2: null,
  },
  methods: {
  }
})

and the template:

<div id="app">
  <input id="testinput1" v-model="testval1" v-test />
  <input id="testinput2" v-model="testval2" v-test />
</div>

Here is a JSFiddle of the issue: https://jsfiddle.net/eywraw8t/415288/

In this JSFiddle, you can see in the console that if you type into the input field, it fires the update for both input fields.

解决方案

I think the best way is to use bind. Your directive there will be a directive that works on every element with v-test directive specified. Here is simple approach to solve your issue

Vue.directive('test', {


  bind: (el) => {
    console.log(el.id + " bound")
    const handler = (e) => {
        console.log('e', e.target)
      if (el == e.target) {
        console.log(el.id + " firing")
      }
    }
    el.vueTest = handler
    // add Event Listeners
    document.addEventListener('input', handler)
  },
  unbind (el, binding) {
    // Remove Event Listeners
    document.removeEventListener('input', el.vueTest);
    el.vueTest = null;
  }
})

Hope this will help you :)

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