vuejs兄弟组件之间的通信

var Event = new Vue();//准备一个空的实例对象
//A组件
var A = {
    template: `
      <div>
        <span>我是A组件的数据->pw_a</span>
        <input type="button" value="把A数据传给C" @click = "send">
      </div>
    `,
    methods: {
      send () {
        Event.$emit("a-msg", this.a);
      }
    },
    data () {
      return {
        a: "我是a组件中数据"
      }
    }
  };
//组件B
  var B = {
    template: `
      <div>
        <span>我是B组件的数据->pw_a</span>
        <input type="button" value="把B数据传给C" @click = "send">
      </div>
    `,
    methods: {
      send () {
        Event.$emit("b-msg", this.a);
      }
    },
    data () {
      return {
        a: "我是b组件中数据"
      }
    }
  };
//组件C
  var C = {
    template: `
      <div>
        <h3>我是C组件</h3>
        <span>接收过来A的数据为: pw_a</span>
        <br>
        <span>接收过来B的数据为: pw_b</span>
      </div>
    `,
    mounted () {
      //接收A组件的数据
      Event.$on("a-msg", function (a) {
        this.a = a;
      }.bind(this));


      //接收B组件的数据
      Event.$on("b-msg", function (a) {
        this.b = a;
      }.bind(this));
    },
    data () {
      return {
        a: "",
        b: ""
      }
    }
  };
  window.onload = function () {
    new Vue({
      el: "#box",
      components: {
        "dom-a": A,
        "dom-b": B,
        "dom-c": C
      }
    });
  };