ES6 数组去重的简单方法

// 数组去重 ES6
    // 1.使用filter去重
    let arr=[2,3,4,3,4,3,4,6];
    let arr1=arr.filter(function(item,index){
        return arr.indexOf(item)===index;
    });
    console.log(arr1);//[ 2, 3, 4, 6 ]
    //2.Set 数组去重
    let item = [1,2,3,3,5,6,6,4];
    let items = new Set([1,2,3,4,6,3,4]);
    let arr = Array.from(items);
    //还可以用于字符串去重
    [...new Set('ababbc')].join('')// "abc"
    //3.使用set add方法去重
    const s = new Set();
    [2, 3, 5, 4, 5, 2, 2].forEach(x => s.add(x));
    let arr3 = Array.from(s);
    console.log(arr3);
    // 4.rest Set 剩余参数去重
    let arr2 = [1,2,3,3,5,6,6,4];
    let arr1=[...new Set(arr)];
    console.log(arr1);//[ 1, 2, 3, 5, 6, 4 ]