What is message subscription and publishing?

Catalog

（1） Introduce

（2） News subscription  

（3） News release

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（1） Introduce

What words do not , Upper figure

Here is the main code of an example ：

（2） News subscription  

Child components 1

  mounted() {
    this.pubId = pubsub.subscribe("haha", function (msgName, data) {
      console.log(" Someone made a move haha news , The callback function is executed ", msgName, data);
    });
  },
  beforeDestroy() {
    pubsub.unsubscribe(this.pubId);
  },

（3） News release

Child components 2

  methods: {
    sendStudentName() {
      // this.getStudentName(this.studentName);
      pubsub.publish("haha", this.studentName);
    },
  },