1.通过npm加载vuex,创建store.js文件,然后在main.js中引入,store.js文件代码如下
import Vue from 'vue'
import Vuex from 'vuex'
Vue.use(Vuex);
const state = {
author:'Wise Wang'
};
const mutations = {
newAuthor(state,msg){
state.author = msg
}
}
export default new Vuex.Store({
state,
mutations
})
2、父组件可以使用 props 把数据传给子组件(props是单向绑定的)。
<div id="app">
<div>这是父组件的parentArray:{{parentArray}}</div>
<my-component :child-array="parentArray"></my-component>
</div>
<script>
Vue.component('my-component', {
template: `
<div>这是接收了父组件传递值的子组件的childArray: {{childArray}} <br>
<button type="button" @click="changeArray">
点击我改变父元素的parentArray</button>
</div>`,
props: ['childArray'],
data () {
return {
counter: 1
}
},
methods: {
changeArray () {
this.childArray.push(this.counter++)
}
}
})
new Vue({
el: '#app',
data: {
parentArray: []
}
})
</script>
3、子组件可以使用 $emit 触发父组件的自定义事件。
vm.$emit( event, arg ) //触发当前实例上的事件
vm.$on( event, fn );//监听event事件后运行 fn;
例如:子组件:
<template>
<div class="train-city">
<h3>父组件传给子组件的toCity:{{sendData}}</h3>
<br/><button @click='select(`大连`)'>点击此处将‘大连’发射给父组件</button>
</div>
</template>
<script>
export default {
name:'trainCity',
props:['sendData'], // 用来接收父组件传给子组件的数据
methods:{
select(val) {
let data = {
cityname: val
};
this.$emit('showCityName',data);//select事件触发后,自动触发showCityName事件
}
}
}
</script>
父组件:
<template>
<div>
<div>父组件的toCity{{toCity}}</div>
<train-city @showCityName="updateCity" :sendData="toCity"></train-city>
</div>
<template>
<script>
import TrainCity from "./train-city";
export default {
name:'index',
components: {TrainCity},
data () {
return {
toCity:"北京"
}
},
methods:{
updateCity(data){//触发子组件城市选择-选择城市的事件
this.toCity = data.cityname;//改变了父组件的值
console.log('toCity:'+this.toCity)
}
}
}
</script>