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 ];
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
如果你不想改变你的数据,考虑这个函数…
renameProp = (oldProp, newProp, { [oldProp]: old, ...others }) => ({
[newProp]: old,
...others
})
Yazeed Bzadough的详细解释 https://medium.com/front-end-hacking/immutably-rename-object-keys-in-javascript-5f6353c7b6dd
下面是一个typescript友好的版本:
// These generics are inferred, do not pass them in.
export const renameKey = <
OldKey extends keyof T,
NewKey extends string,
T extends Record<string, unknown>
>(
oldKey: OldKey,
newKey: NewKey extends keyof T ? never : NewKey,
userObject: T
): Record<NewKey, T[OldKey]> & Omit<T, OldKey> => {
const { [oldKey]: value, ...common } = userObject
return {
...common,
...({ [newKey]: value } as Record<NewKey, T[OldKey]>)
}
}
它将防止您破坏现有的键或将其重命名为相同的东西
其他回答
还有一种最强大的REDUCE方法。
数据= {\ key1:“value1”,key2:“value2”,key3:“value3”}; 键文件夹= {\ key1:“firstkey”,key2:“secondkey”,key3:“thirdkey” mappedData = Object.keys . .还原((obj,k) =>对象。assign(obj, {\ [keyMap]]:数据[k]},{\}; 控制台日志(mappedData); 第一个“value1”、“secondkey”、“value2”、“thirdkey”、“value3”……
const data = res
const lista = []
let newElement: any
if (data && data.length > 0) {
data.forEach(element => {
newElement = element
Object.entries(newElement).map(([key, value]) =>
Object.assign(newElement, {
[key.toLowerCase()]: value
}, delete newElement[key], delete newElement['_id'])
)
lista.push(newElement)
})
}
return lista
我认为最完整(和正确)的方法是:
if (old_key !== new_key) {
Object.defineProperty(o, new_key,
Object.getOwnPropertyDescriptor(o, old_key));
delete o[old_key];
}
此方法确保重命名的属性的行为与原始属性相同。
另外,在我看来,把它包装成一个函数/方法,并把它放入对象的可能性。原型与你的问题无关。
如果你想保留迭代顺序(插入的顺序),这里有一个建议:
const renameObjectKey = (object, oldName, newName) => {
const updatedObject = {}
for(let key in object) {
if (key === oldName) {
newObject[newName] = object[key]
} else {
newObject[key] = object[key]
}
}
object = updatedObject
}
您可以将工作包装在一个函数中,并将其分配给Object原型。也许可以使用流畅的界面样式使多个重命名流动。
Object.prototype.renameProperty = function (oldName, newName) {
// Do nothing if the names are the same
if (oldName === newName) {
return this;
}
// Check for the old property name to avoid a ReferenceError in strict mode.
if (this.hasOwnProperty(oldName)) {
this[newName] = this[oldName];
delete this[oldName];
}
return this;
};
ECMAScript 5 Specific
我希望语法不是这么复杂,但它肯定是很好的有更多的控制。
Object.defineProperty(
Object.prototype,
'renameProperty',
{
writable : false, // Cannot alter this property
enumerable : false, // Will not show up in a for-in loop.
configurable : false, // Cannot be deleted via the delete operator
value : function (oldName, newName) {
// Do nothing if the names are the same
if (oldName === newName) {
return this;
}
// Check for the old property name to
// avoid a ReferenceError in strict mode.
if (this.hasOwnProperty(oldName)) {
this[newName] = this[oldName];
delete this[oldName];
}
return this;
}
}
);