如何基于另一个对象数组创建一个对象数组？

Question

我有这个数组：

var arr1 = [
 {"user":"dan","liked":"yes","age":"22"},
 {"user":"sarah","liked":"no","age":"21"},
 {"user":"john","liked":"yes","age":"23"},
];

我想创建该数组的新（子）数组，仅包含用户的喜好。

所以它看起来像这样：

var arr2 = [
 {"dan":"yes"},
 {"sarah":"no"},
 {"john":"yes"},
];

我试过：

var arr2 =[];
for(var i in arr1){
  arr2.push({[i[user]]:i[liked]});
}

它需要调整，想法？

Answer 1

使用array.map

 var arr1 = [ {"user":"dan","liked":"yes","age":"22"}, {"user":"sarah","liked":"no","age":"21"}, {"user":"john","liked":"yes","age":"23"}, ]; var arr2 = arr1.map(v => ({ user: v.user, liked: v.liked })); console.log(arr2);

对于您的更新，虽然可以使用array.map完成， array.map我建议您改用键值对结构。 你需要array.reduce 。

 var arr1 = [ {"user":"dan","liked":"yes","age":"22"}, {"user":"sarah","liked":"no","age":"21"}, {"user":"john","liked":"yes","age":"23"}, ]; var arr2 = arr1.reduce((c, v) => (c[v.user] = v.liked, c) , {}); console.log(arr2);

Answer 2

根据您的编辑：

 arr1 = arr1.map(function(item){ return{ [item.user]: item.liked } });

Answer 3

 var arr1 = [ {"user":"dan","liked":"yes","age":"22"}, {"user":"sarah","liked":"no","age":"21"}, {"user":"john","liked":"yes","age":"23"}, ]; var res = arr1.map(function(o) { var r = {}; r[o.user] = o.liked; return r; }); console.log(res);

或者在最近的 ECMAScript 版本中：

 var arr1 = [ {"user":"dan","liked":"yes","age":"22"}, {"user":"sarah","liked":"no","age":"21"}, {"user":"john","liked":"yes","age":"23"}, ]; var res = arr1.map(o => ( { [o.user]: o.liked } )); console.log(res);

Answer 4

尝试这个

var arr2 =[];
for(var i in arr1){
    var obj= {};
    obj[arr1[i]['user']] = arr1[i]['liked'];
    arr2.push(obj)
} 

Answer 5

var arr2=[];
arr1.forEach(function(obj)
{
    var temp=new Object();
    temp[obj.user]=obj.liked;
    arr2.push(temp);
});

我想这就是你想要的

Answer 6

您可以将解构的所需属性映射到新对象。

 var array1 = [{ user: "dan", liked: "yes", age: "22" }, { user: "sarah", liked: "no", age: "21" }, { user: "john", liked: "yes", age: "23" }], array2 = array1.map(({ user, liked }) => ({ [user]: liked })); console.log(array2);

ES5

 var array1 = [{ user: "dan", liked: "yes", age: "22" }, { user: "sarah", liked: "no", age: "21" }, { user: "john", liked: "yes", age: "23" }], array2 = array1.map(function (o) { var temp = {}; temp[o.user] = o.liked; return temp; }); console.log(array2);

Answer 7

如果它是一个对象数组

var arr1=[{},{},..]

你必须遍历对象属性，所以你需要这个

var arr2 =[]



 arr1.forEach(element => {
      var temp = new Object();
      for (var name in element) {
        temp[name] = element[name]
      }
      arr2 .push(temp)
    });

现在你有 arr2 作为不同于 arr1 的另一个对象