vue data赋值赋不上去

Question

export default {
  name: 'SidebarMenu',
  props: {item: {}},
  data () {
    return {
      menuList: [{}]
    }
  },
  created: function () {
    this.getMenuList()
  },
  methods: {

    getMenuList (event) {
      $.getJSON('/cost-manager/sys/menu/user?_' + $.now(), function (r) {
        // console.log(r)
        this.menuList = r.menuList

      })
    }
  }
}

*
menuList始终为空，赋值赋不上去，求解

*

Answer 1

在getjson外声明 var _self = this; _self.menuList = r.menu.List;

Answer 2

This binding rule:

1. Default Binding

2. Implicit Binding

3. Explicit Binding

4. new Binding

强烈建议对this不了解的看下YDKJS的这篇文章

Answer 3

这里 this 指向不对，应该使用箭头函数：

$.getJSON('xx', (res) => {
    this.menuList
})