JS数组去重

1、ES6语法filter()去重

let arr = ['灭绝师太','周芷若','小龙女','郭襄','小龙女'];
     arr = arr.filter((item,index) => arr.indexOf(item) == index);
    console.log(arr)
  //['灭绝师太','周芷若','小龙女','郭襄']

2、ES6语法new Set()去重

let arr = ['灭绝师太','周芷若','小龙女','郭襄','小龙女'];
     arr = Array.from(new Set(arr))
     console.log(arr)
//['灭绝师太','周芷若','小龙女','郭襄']