对象的 Javascript 数组 - 按特定键的唯一性过滤，并仅保留某些键

Question

我敢肯定这个问题以前曾在这里以某种形式被问过，但我找不到正确的解决方案。我有一个这样的对象数组:

[
  {id:"124", name:"Joe", lname:"Smith", age:"14"},
  {id:"124", name:"Joe", lname:"Smith", age:"17"},
  {id:"124", name:"Joe", lname:"Smith", age:"21"},
  {id:"128", name:"Tom", lname:"Cans", age:"18"},
  {id:"132", name:"Mik", lname:"Brak", age:"21"}
];

我想缩短此数组，使其仅包含具有唯一 id 键的对象，以及仅包含键 id、name、lname 的对象。我想要的输出是:

 [
   {id:"124", name:"Joe", lname:"Smith"},
   {id:"128", name:"Tom", lname:"Cans"},
   {id:"132", name:"Mik", lname:"Brak"}
 ];

到目前为止我所做的 - 我可以使用以下代码片段创建一个唯一 ID 数组，但这并没有让我到达我需要去的地方:

 let uniqueIDs = [... new Set(mydata.map(val => val.id))];

感谢任何帮助!!

Answer 1

将你的数组项存储在一个对象中，由 id 索引，并跳过任何你已经拥有的:

var obj = {}
[ {id:"124", name:"Joe", lname:"Smith", age:"14"},
  {id:"124", name:"Joe", lname:"Smith", age:"17"},
  {id:"124", name:"Joe", lname:"Smith", age:"21"},
  {id:"128", name:"Tom", lname:"Cans", age:"18"},
  {id:"132", name:"Mik", lname:"Brak", age:"21"}
].forEach(function(d){
  if ( ! obj[d.id] ) {
    // omit the info you're not interested in
    obj[d.id] = { id: d.id, name: d.name, lname: d.lname } 
  }
})
var uniq = Object.values(obj);
console.log(uniq)