Vue2.0 Vue.set() method

focus:

You can use the vueone given to you apito implement the added data and also have a responsive function, called: Vue.set(), set()which can pass three parameters: f(target,key,val), target: 目标(你要往谁的身上追加一个属性), key: 你要往它的身上追加一个什么名字的属性, val:这个属性的值

Vue.set and vm.$set