数组去重排序

第一种去重排序---[...new Set(arr)]

　　[...new Set([1,true,15,false,undefined,null,NaN,"NaN",0,"a",{},{}])].sort(function(a,b){return a-b})

数组交集]

[2,4,5,6,8,6].filter(item=>[4,5,8].indexOf(item)>-1)