itg

递归中，调⽤forEach⽅法问题

1functiontraver(objNmae,obj,url){

2url=url||objNmae;

3if(typeofobj==="object"){

4//forin⽅法

5for(letiinobj){

6url+=("=>"+i);

(i,obj[i],url);

8}

9//forEach⽅法

h(function(value,index){

11url+=("=>"+index);

(index,value,url);

13});

14}elif(typeofobj==="string"||typeofobj==="number"){

(url+objNmae+":"+obj);

16return;

17}

18}

forin⽅法和forEach⽅法，⽅法的功能是同样的，就是遍历⼀个对象集，并且输出对象中所有末端元素的路径。

接下来我们对下⾯的这个对象进⾏遍历

varitg_data=

[{"itg_num":"1200","itg_category":"rew_gold","itg_reward_num":"1","itg_sum_num":"661","itg_place":"","pic":"Uploadsgamereward3572

","goods_unit":"u679a","goods_name":null},

{"itg_num":"1400","itg_category":"rew_goods","itg_reward_num":"4","itg_sum_num":"656","itg_place":"fresh","pic":"UploadsUploadsShop2017-07-

","goods_unit":"u679a","goods_name":"u65e0u6297u571fu9e21u86cb"},

{"itg_num":"1600","itg_category":"rew_gold","itg_reward_num":"2","itg_sum_num":"555","itg_place":"","pic":"Uploadsgamereward3572

","goods_unit":"u679a","goods_name":null},

{"itg_num":"1800","itg_category":"rew_goods","itg_reward_num":"8","itg_sum_num":"492","itg_place":"fresh","pic":"UploadsUploadsShop2017-07-

","goods_unit":"u679a","goods_name":"u65e0u6297u571fu9e21u86cb"},

{"itg_num":"2500","itg_category":"rew_goods","itg_reward_num":"1","itg_sum_num":"555","itg_place":"fresh","pic":"UploadsUploadsShop2017-06-

","goods_unit":"u53ea","goods_name":"u6bcdu9e21uff08u6563u517buff09"}];

forin⽅法

但是在这⾥forEach⽅法会报错，

提⽰最⼤调⽤栈⼤⼩超过。但是使⽤forin就没有这样的问题

由此可见，forEach在递归中因为，有些对象树过深，对导致其堆栈溢出，forEach不适合⽤在递归中，可以使⽤forin