javascript - 用javascript中另一个对象的值创建新对象

Question

我们如何使用 JavaScript 更改以下数据对象的结构。需要将所有名称分类到std下。提前致谢

[
    {
        "name": "Rohan",
        "std": "3"
    },
    {
        "name": "Jack",
        "std": "2"
    },
    {
        "name": "Peter",
        "std": "2"
    }
]

到

[
    {
        "std": "2",
        "details": [
            {
                "name": "Jack"
            },
            {
                "name": "Peter"
            }
        ]
    },
    {
        "std": "3",
        "details": [
            {
                "name": "Rohan"
            }
        ]
    }
]

Answer 1

使用Array.forEach、Array.map和Object.keys函数的解决方案:

var arr = [{"name": "Rohan", "std": "3"}, { "name": "Jack", "std": "2" }, { "name": "Peter", "std": "2" }],
    grouped = {}, result;

arr.forEach(function(obj){
    var std = obj['std'];
    if (this[std]) {
        this[std]['details'].push({'name' : obj['name']});
    } else {
        this[std] = {'std' : std, 'details' : [{'name' : obj['name']}]};
    }
}, grouped);
result = Object.keys(grouped).map((k) => grouped[k]);

console.log(JSON.stringify(result, 0, 4));

输出:

[
    {
        "std": "2",
        "details": [
            {
                "name": "Jack"
            },
            {
                "name": "Peter"
            }
        ]
    },
    {
        "std": "3",
        "details": [
            {
                "name": "Rohan"
            }
        ]
    }
]