JavaScript Object。 更改数组中对象的键名

Question

我有一个像这个例子一样的对象数组：

[
  { id: 44, message: 'abcd', name: 'example1' },
  { id: 44, message: 'efgh', name: 'example2' },
  { id: 45, message: 'ijkl', name: 'example3' },
  { id: 45, message: 'mnop', name: 'example4' },
]

如您所见， id 值是重复的。 现在我只需要在第二次重复 object 时将“name”的键名更改为“lastName”：

[
  { id: 44, message: 'abcd', name: 'example1' },
  { id: 44, message: 'efgh', lastName: 'example2' },
  { id: 45, message: 'ijkl', name: 'example3' },
  { id: 45, message: 'mnop', lastName: 'example4' },
]

Answer 1

您可以保留last id跟踪，并在map loop中modify返回 object

对于未排序的列表：

 let data = [ { id: 44, message: "abcd", name: "example1" }, { id: 44, message: "efgh", name: "example2" }, { id: 45, message: "ijkl", name: "example3" }, { id: 45, message: "mnop", name: "example4" }, ]; let idMap = new Set(); const result = data.map((item) => { if (idMap.has(item.id)) { const { name: lastName, ...rest } = item; item = {...rest, lastName }; } else { idMap.add(item.id); } return item; }); console.log(result);

注意：数据必须根据 id 进行排序。

 let data = [ { id: 44, message: "abcd", name: "example1" }, { id: 44, message: "efgh", name: "example2" }, { id: 45, message: "ijkl", name: "example3" }, { id: 45, message: "mnop", name: "example4" }, ]; let lastId = ""; const result = data.map((item) => { if (lastId === item.id) { const { name: lastName, ...rest } = item; item = {...rest, lastName }; lastId = ""; } else { lastId = item.id; } return item; }); console.log(result);

Answer 2

如果具有此 id 的项目已被访问，您可以保存每个项目的id并将键从name重命名为lastName 。

 let list = [ { id: 44, message: 'abcd', name: 'example1' }, { id: 44, message: 'efgh', name: 'example2' }, { id: 45, message: 'ijkl', name: 'example3' }, { id: 45, message: 'mnop', name: 'example4' }, ]; let checked = []; list.forEach(function (item) { if(checked.includes(item.id)){ item['lastName'] = item['name']; delete item['name']; }else{ checked.push(item.id); } }); console.log(list)