javascript - 将一个 json 对象注入(inject)/复制到另一个 json 对象中以扩展它们

Question

如何使用 javascript/nodejs 执行以下操作:

注入(inject)json结果A(只有一个json对象)

[{
    "user": "userA",
    "group": "groupA"
}]

转换为json结果B(具有相同结构的多个json对象)

[{
    "picture": "picA",
    "city": "cityA",
    "year": "2016"
},
{
    "picture": "picB",
    "city": "cityB",
    "year": "2017"
}]

将 A 注入(inject) B 后创建以下所需的 json 对象 C

[{
    "user": "userA",
    "group": "groupA",
    "picture": "picA",
    "city": "cityA",
    "year": "2016"
},
{
    "user": "userA",
    "group": "groupA",
    "picture": "picB",
    "city": "cityB",
    "year": "2017"
}]

我需要合并两个 json 结果。但对象 A 应该复制到所有 B 对象中以扩展它们。

Answer 1

由于您只有基元，因此如果存在重复的属性名称，以下内容将合并属性而不覆盖:

let toBeCopied = [{
    "user": "userA",
    "group": "groupA"
}];

let result = [{
    "picture": "picA",
    "city": "cityA",
    "year": "2016"
},
{
    "picture": "picB",
    "city": "cityB",
    "year": "2017"
}];

let merged = result.map(r => Object.assign({}, toBeCopied[0], r));

如果您想覆盖旧数组的元素(而不是创建新数组)，请执行以下操作:

for (let i = 0; i < result.length; i++) {
    result[i] = Object.assign({}, toBeCopied[0], result[i]);
}

但是，如果将来任何属性都是对象，请记住只会复制对象引用(不会深度克隆)。