对比两组对象数组 根据元素内某一属性是否相等过滤数组
from:https://segmentfault.com/q/1010000017464256
arr2.filter(item => arr1.find(_item => item.a === _item.a && item.b === _item.b))
from:https://segmentfault.com/q/1010000017464256
arr2.filter(item => arr1.find(_item => item.a === _item.a && item.b === _item.b))