js数据结构转换

Question

如何用ES5将形如以下的数据结构:[{obj0:"2016-12-01",obj1:"交通事故",obj2:"218"},{obj0:"2016-12-01",obj1:"医疗事故",obj2:"1"},{obj0:"2016-12-02",obj1:"交通事故",obj2:"200"},{obj0:"2016-12-02",obj1:"医疗事故",obj2:"5"}]转化成[{'2016-12-01':['交通事故':'218','医疗事故':'1']},{'2016-12-02':['交通事故':'200','医疗事故':'5']}]这样的结构呢?

Answer 1

let data = [{obj0:"2016-12-01",obj1:"交通事故",obj2:"218"},{obj0:"2016-12-01",obj1:"医疗事故",obj2:"1"},{obj0:"2016-12-02",obj1:"交通事故",obj2:"200"},{obj0:"2016-12-02",obj1:"医疗事故",obj2:"5"}],

    res = {};

for (let item of data) {

    let obj = res[item.obj0] || {};

    obj[item.obj1] = item.obj2;

    res[item.obj0] = obj;

}

console.log(JSON.stringify(res))

// {"2016-12-01":{"交通事故":"218","医疗事故":"1"},"2016-12-02":{"交通事故":"200","医疗事故":"5"}}