对象和数组

 1 let obj = {
 2     name:"张三",
 3     age:18,
 4     like:"音乐，电影"
 5 };
 6 let ary = ["chinese",80,"math",90,"english",85];
 7 
 8 
 9 //数组转对象：
10 function ao(ary){
11     let obj1 = {};
12     for(let i=0;i<ary.length;i++){
13         let cur = ary[i];
14         let curn = ary[i+1];
15         if(i%2===0 && (i+1)%2===1){
16             obj1[cur] = curn;
17         }
18     }
19     return obj1;
20 }

21 console.log(ao(ary));

如果数组的格式是[{name:'abc',age:18},{name:'efg',age:20},{name:'hij',age:21}] 
遍历数组的每一项，拿出每一项的name作为obj1的key，拿出每一项的age作为value，就是将数组每一项改造为key:value的形式存入对象

22

23 //对象转数组：
24 function oa(obj){
25     let ary1 = [];
26     for(let key in obj){
27         if(obj.hasOwnProperty(key)){
28             ary1.push(key);//属性名
29             ary1.push(obj[key]);//属性值
30         }
31     }
32     return ary1;
33 }
34 console.log(oa(obj));
35 
36 //数组克隆：
37 let ary1 = ary.concat();
38 ary1.pop();
39 console.log(ary1,ary);
40 
41 //对象克隆：
42 let obj1 = {};
43 for(let key in obj){
44     if(obj.hasOwnProperty(key)){
45         obj1[key] = obj[key];
46     }
47 }
48 obj1.name="李四";
49 console.log(obj1,obj);
50 
51 
52 
53 console.log(ao(oa(ao(ary))));

深度克隆

 1 function deepClone(obj){
 2   let newObj = Array.isArray(obj) ? [] : {};
 3   if(obj && typeof obj === 'object'){
 4      for(let key in obj){
 5         if(obj.hasOwnProperty(key)){
 6             newObj[key] = (obj && typeof obj[key] === 'object') ? deepClone(obj[key]) : obj[key];
 7         }
 8     }   
 9   }
10   return newObj;    
11 }

jq的each方法

    var obj = {
        name:'asdf',
        age:12,
        sex:0
    };
    var ary = [12,23,34,45];
    //jq遍历数组两种方法结果一样
    $.each(ary,function(index,item){
        console.log(index,item)
    })
    $(ary).each(function(index,item){
        console.log(index,item)
    })
    //jq遍历对象只能用这种方法
    $.each(obj,function(key,value){
        console.log(key,value)
    })