是否有一个聪明的(即优化)方法重命名一个关键在javascript对象?

一种非优化的方式是:

o[ new_key ] = o[ old_key ];
delete o[ old_key ];

当前回答

一般来说,如果你想获得一个新的对象(不改变原来的对象),根据keyMap重命名键-你可以使用以下基于lodash mapKeys的实现:

const {mapKeys} = require('lodash');
const renameKeys = (obj, keyMap) => _.mapKeys(obj, (value, key) => keyMap[key] || key);

使用的例子:

renameKeys({a: 1, b: 2, c: 3}, {c: 'p', a: 'm'})
> {m: 1, b: 2, p: 3}

其他回答

function iterate(instance) {
  for (let child of instance.tree_down) iterate(child);

  instance.children = instance.tree_down;
  delete instance.tree_down;
}

iterate(link_hierarchy);

console.log(link_hierarchy);

为每个键添加前缀:

const obj = {foo: 'bar'}

const altObj = Object.fromEntries(
  Object.entries(obj).map(([key, value]) => 
    // Modify key here
    [`x-${key}`, value]
  )
)

// altObj = {'x-foo': 'bar'}

重命名对象键的另一种方法:

让我们考虑这个对象:

let obj = {"name": "John", "id": 1, "last_name": "Doe"}

让我们重命名name key为first_name:

let { name: first_name, ...rest } = obj;
obj = { first_name, ...rest }

现在对象是:

{"first_name": "John", "id": 1, "last_name": "Doe"}

虽然这并不是一个更好的重命名键的解决方案,但它提供了一种快速简单的ES6方法来重命名对象中的所有键,同时不改变它们所包含的数据。

let b = {a: ["1"], b:["2"]};
Object.keys(b).map(id => {
  b[`root_${id}`] = [...b[id]];
  delete b[id];
});
console.log(b);

使用对象解构和展开运算符的变体:

const old_obj = {
    k1: `111`,
    k2: `222`,
    k3: `333`
};    

// destructuring, with renaming. The variable 'rest' will hold those values not assigned to kA, kB, or kC.
const {
    k1: kA, 
    k2: kB, 
    k3: kC,
    ...rest
} = old_obj;
    

// now create a new object, with the renamed properties kA, kB, kC; 
// spread the remaining original properties in the 'rest' variable
const newObj = {kA, kB, kC, ...rest};

对于一个键,这可以很简单:

const { k1: kA, ...rest } = old_obj;
const new_obj = { kA, ...rest }

你也可能喜欢更“传统”的风格:

const { k1, ...rest } = old_obj
const new_obj = { kA: k1, ...rest}