js回调函数原理与用法案例分析

<script language="javascript" type="text/javascript">
function doSomething(callback) {
  // 调用回调函数
  callback('我', '网名', '叶落森');
}
function foo(a, b, c) {
  //这是回调函数
  alert(a + " " + b + " " + c);
}
doSomething(foo);
</script>

import {mapActions, mapGetters} from 'vuex';
export default {
  name: 'role',
  data () {
    return {

    };
  },
  computed: {},
  methods: {
    ...mapActions(['getRoleData', 'getPowerData']),
      callbackFn(type,content){//这是回调函数
        if(type){
          this.$Message.success(content)
        }else{
          this.$Message.error({
            content: content,
            duration: 5
          })
        }
      },
      initRoleId () {
         this.getRoleData({path:'http://www.baidu.com/',callbackFn:this.callbackFn});
      }
  },
  mounted(){
    this.initRoleId();
  }
};

actions: {
    getRoleData ({commit}, {path,callbackFn}) {
      axios.get(path + 'roles', {params: {pageSize: 500}}).then(res => {
        if(res.data.retCode=="200"){
          commit('ROLE_DATA', {roleData: res.data.data.records});
        }else{
          callbackFn(0,res.data.message)//调用回调函数
        }
      });
    },
}