javascript - JavaScript 数组与对象的对称差异

Question

let arr1 = [{ countryCode: "ITA", index: 2, name: "Italy"}, { countryCode: "NLD", index: 1, name: "Netherlands"}];

let arr2 = [{ countryCode: "NLD", index: 1, name: "Netherlands"}, { countryCode: "BEL", index: 3, name: "Belgium"}];

我希望它返回对称差，所以它应该返回:

[{ countryCode: "ITA", index: 2, name: "Italy"},  {countryCode: "BEL", index: 3, name: "Belgium"}]

如何在 JavaScript 中完成此操作？我尝试执行以下操作:

let difference = arr1
                 .filter(x => !arr2.includes(x))
                 .concat(arr2.filter(x => !arr1.includes(x))); 

但这似乎不适用于其中包含对象的数组。

Answer 1

您可以获取 map 并添加或删除该项目(如果该项目位于 map 中)。

const
    array1 = [{ countryCode: "ITA", index: 2, name: "Italy"}, { countryCode: "NLD", index: 1, name: "Netherlands" }],
    array2 = [{ countryCode: "NLD", index: 1, name: "Netherlands" }, { countryCode: "BEL", index: 3, name: "Belgium" }],
    map = new Map,
    cb = o => map.delete(o.countryCode) || map.set(o.countryCode, o);

array1.forEach(cb);
array2.forEach(cb);

console.log(Array.from(map.values()));