如何在v模型更改时触发事件？(vue js)

Question

我正在尝试使用该foo()功能,@click但正如您所见,需要按两次单选按钮才能正确触发事件.只有第二次按下时才能捕捉到该值...

我希望@click在v-model(srStatus)更改时触发事件而不仅仅触发事件.

这是我的小提琴:

http://fiddle.jshell.net/wanxe/vsa46bw8/

Answer 1

您可以通过删除v-on指令来实际简化:

<input type="radio" name="optionsRadios" id="optionsRadios1" value="1" v-model="srStatus">

并使用该watch方法来监听更改:

new Vue ({
    el: "#app",
    data: {
        cases: [
            { name: 'case A', status: '1' },
            { name: 'case B', status: '0' },
            { name: 'case C', status: '1' }
        ],
        activeCases: [],
        srStatus: ''
    },
    watch: {
        srStatus: function(val, oldVal) {
            for (var i = 0; i < this.cases.length; i++) {
                if (this.cases[i].status == val) {
                    this.activeCases.push(this.cases[i]);
                    alert("Fired! " + val);
                }
            }
        }
    }
});

Answer 2

发生这种情况是因为您的click处理程序在单选按钮的值更改之前触发.你需要听取这个change事件:

<input 
  type="radio" 
  name="optionsRadios" 
  id="optionsRadios2" 
  value=""
  v-model="srStatus" 
  v-on:change="foo"> //here

此外,确保你真的想要foo()准备就绪......看起来也许你真的不想这样做.

ready:function(){
    foo();
},

Answer 3

Vue2:如果你只想检测输入模糊的变化(例如在按下回车或点击其他地方之后)(这里有更多信息)

<input @change="foo" v-model... >

如果您想检测单个字符更改(在用户输入期间)使用

<input @keydown="foo" v-model... >

您还可以使用@keyup和@input事件.如果你想在模板中使用其他参数,例如 @keyDown="foo($event, param1, param2)".下面的比较(此处可编辑版本)

new Vue({
  el: "#app",
  data: { 
    keyDown: { key:null, val: null,  model: null, modelCopy: null },
    keyUp: { key:null, val: null,  model: null, modelCopy: null },
    change: { val: null,  model: null, modelCopy: null },
    input: { val: null,  model: null, modelCopy: null },
    
    
  },
  methods: {
  
    keyDownFun: function(event){                   // type of event: KeyboardEvent   
      console.log(event);  
      this.keyDown.key = event.key;                // or event.keyCode
      this.keyDown.val = event.target.value;       // html current input value
      this.keyDown.modelCopy = this.keyDown.model; // copy of model value at the moment on event handling
    },
    
    keyUpFun: function(event){                     // type of event: KeyboardEvent
      console.log(event);  
      this.keyUp.key = event.key;                  // or event.keyCode
      this.keyUp.val = event.target.value;         // html current input value
      this.keyUp.modelCopy = this.keyUp.model;     // copy of model value at the moment on event handling
    },
    
    changeFun: function(event) {                   // type of event: Event
      console.log(event);
      this.change.val = event.target.value;        // html current input value
      this.change.modelCopy = this.change.model;   // copy of model value at the moment on event handling
    },
    
    inputFun: function(event) {                    // type of event: Event
      console.log(event);
      this.input.val = event.target.value;         // html current input value
      this.input.modelCopy = this.input.model;     // copy of model value at the moment on event handling
    }
  }
})

div {
  margin-top: 20px;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>

Type in fields below (to see events details open browser console)

<div id="app">
  <div><input type="text" @keyDown="keyDownFun" v-model="keyDown.model"><br> @keyDown (note: model is different than value and modelCopy)<br> key:{{keyDown.key}}<br> value: {{ keyDown.val }}<br> modelCopy: {{keyDown.modelCopy}}<br> model: {{keyDown.model}}</div>
  
  <div><input type="text" @keyUp="keyUpFun" v-model="keyUp.model"><br> @keyUp (note: model change value before event occure) <br> key:{{keyUp.key}}<br> value: {{ keyUp.val }}<br> modelCopy: {{keyUp.modelCopy}}<br> model: {{keyUp.model}}</div>
  
  <div><input type="text" @change="changeFun" v-model="change.model"><br> @change (occures on enter key or focus change (tab, outside mouse click) etc.)<br> value: {{ change.val }}<br> modelCopy: {{change.modelCopy}}<br> model: {{change.model}}</div>
  
  <div><input type="text" @input="inputFun" v-model="input.model"><br> @input<br> value: {{ input.val }}<br> modelCopy: {{input.modelCopy}}<br> model: {{input.model}}</div>
     
</div>

Answer 4

您应该使用@input：

<input @input="handleInput" />

@input 用户更改输入值时触发。

@change 当用户更改值和未聚焦输入（例如在外部某处单击）时触发

您可以在这里看到区别：https : //jsfiddle.net/posva/oqe9e8pb/

Answer 5

只是为了添加上面的正确答案,在Vue.JS v1.0中你可以写

<a v-on:click="doSomething">

所以在这个例子中它会是

 v-on:change="foo"

请参阅:http://v1.vuejs.org/guide/syntax.html#Arguments