Javascript：合并笛卡尔对象数组

Question

我有以下对象数组

{
 "roleid":[{"rolename":[1639]}],
 "modnameid":[{"mname":[1516,1515,1514]}],
 "accesstype":[{"accesstype":["VO","AA"]}]
}

我想把它转换成下面的格式

[
{"modnameid":1516,"accesstype":"VO","roleid":1639},
{"modnameid":1516,"accesstype":"AA","roleid":1639},
{"modnameid":1515,"accesstype":"VO","roleid":1639},
{"modnameid":1515,"accesstype":"AA","roleid":1639},
{"modnameid":1514,"accesstype":"VO","roleid":1639},
{"modnameid":1514,"accesstype":"AA","roleid":1639}
]

我们如何着手，基本假设什么是基于多层地图的操作，值得深思感谢您的帮助！

Answer 1

可以用户

let data = {
    "roleid": [{ "rolename": [1639] }],
    "modnameid": [{ "mname": [1516, 1515, 1514] }],
    "accesstype": [{ "accesstype": ["VO", "AA"] }]
}
let roles = []
data.roleid.forEach(element => {
    roles = [...roles, ...element.rolename]
});

let names = []
data.modnameid.forEach(element => {
    names = [...names, ...element.mname]
});

let types = []
data.accesstype.forEach(element => {
    types = [...types, ...element.accesstype]
});

let informations = []
roles.forEach(role => {
    names.forEach(name => {
        types.forEach(type => {
            informations.push({ "modnameid": role, "accesstype": type, "roleid": name })
        });
    });
});

console.log(informations);

Answer 2

除了硬编码答案之外，您还可以采用动态方法，首先获取具有平面数据数组的对象，然后构建笛卡尔积数组。

function getCartesian(object) {
    return Object.entries(object).reduce((r, [k, v]) => {
        var temp = [];
        r.forEach(s =>
            (Array.isArray(v) ? v : [v]).forEach(w =>
                (w && typeof w === 'object' ? getCartesian(w) : [w]).forEach(x =>
                    temp.push(Object.assign({}, s, { [k]: x }))
                )
            )
        );
        return temp;
    }, [{}]);
}

const
    data = { roleid: [{ rolename: [1639] }], modnameid: [{ mname: [1516, 1515, 1514] }], accesstype: [{ accesstype: ["VO", "AA"] }] },
    flat = v => v && typeof v === 'object'
        ? Object.values(v).flatMap(flat)
        : v;
    temp = Object.fromEntries(Object.entries(data).map(([k, v]) => [k, flat(v)]));

console.log(temp);
console.log(getCartesian(temp));

.as-console-wrapper { max-height: 100% !important; top: 0; }

Javascript：合并笛卡尔对象数组

Javascript: merge cartesian array of objects

javascript

arrays

ecmascript-6

array-merge

cartesian-product