Go deep into the principle of corresponding change

Official Website: Principle of Corresponding Change

var vm = new Vue({
    
    
  data:{
    
    
    a:1
  }
})

// `vm.a` 是响应式的

vm.b = 2
// `vm.b` 是非响应式的

• Object: You can use vue.set(), or this.$set(), to change
• Array: You can also use set to achieve, and some variant array methods to achieve