ES6数组去重、快速去重排序

new Set()方法

var  arr = [1,2,1,2,3,4,5,6,6,9,9,8];
console.log(new Set(arr))

Array.from(new Set(arr))方法

var  arr = [1,2,1,2,3,4,5,6,6,9,9,8];
console.log(Array.from(new Set(arr))

BFC:块级元素格式化上下文

浅拷贝

var   a = {
    name = 1
}
b=a;
b.name = 2
console.log(a) //2

深拷贝

var newObj = {};
    function deepCopy(obj,newObj){
    for(var i in obj){
        if(typeof(obj[i]) === "object"){//判断这个是否为对象或者是数组
            newObj[i] = Array.isArray(obj[i])?[]:{};//newObj.arr={}
            deepCopy(obj[i],newObj[i]);//用递归把数组或者数组中的每一个元素遍历出来
                    }else{      
                        newObj[i] = obj[i];//newObj.name=bgg
                    }
                }
                return newObj;
            }
            var res = deepCopy(obj1,newObj);
            console.log(res);
//改变obiect
            res.skill = function(){
                console.log("9999");
            }
            obj1.skill();
            res.skill();
            res.arr[0] = "888";
            console.log(obj1.arr);
            console.log(res.arr);