javascript - 使用javascript使用两个数组中的不同值创建对象数组

Question

我的问题有点复杂。我有两个数据数组:

var arr = [
  {title: "foo", namesIndices: [0,1]},
  {title: "bar", namesIndices: [2]},
  {title: "baz", namesIndices: [3,4]}
];

var names = [
  {name: "John", website: "someUrl"},
  {name: "Mike", website: "someUrl"},
  {name: "Jane", website: "someUrl"},
  {name: "Ali", website: "someUrl"},
  {name: "Robert", website: "someUrl"}
];

其中，namesIndices 将引用名称数组中的索引，该索引将与该人及其头衔相对应。为了将人名和网站与正确的标题相匹配来制作此数组:

var person = [
  {name: "John", title: "foo", website: "someUrl"},
  {name: "Mike", title: "foo", website: "someUrl"},
  {name: "Jane", title: "bar", website: "someUrl"},
  {name: "Ali", title: "baz", website: "someUrl"},
  {name: "Robert", title: "baz", website: "someUrl"}
];

我必须循环第一个数组，然后循环 arr.namesIndices:

var person = [];
for (var i = 0; i < arr.length; i++) {
    for (var j = 0; j < arr[i].namesIndices.length; j++) {
        var personObj = {};
        personObj.title= arr[i].title;
        personObj.name = names[arr[i].namesIndices[j]].name;
        personObj.website= names[arr[i].namesIndices[j]].website;
        person.push(personObj);
     }
 }

有没有办法在没有嵌套循环的情况下做到这一点？

Answer 1

如果您愿意，您可以使用 reduce() 和 map() 来完全避免显式循环。

var arr = [
  {title: "foo", namesIndices: [0,1]},
  {title: "bar", namesIndices: [2]},
  {title: "baz", namesIndices: [3,4]}
];

var names = [
  {name: "John", website: "someUrl"},
  {name: "Mike", website: "someUrl"},
  {name: "Jane", website: "someUrl"},
  {name: "Ali", website: "someUrl"},
  {name: "Robert", website: "someUrl"}
];

var person = arr.reduce(function (accumulator, titleAndIndices, arrIndex) {
    var newEntries = titleAndIndices.namesIndices.map(function (index) {
        var rv = names[index];
        rv.title = arr[arrIndex].title;
        return rv;
    });
    return accumulator.concat(newEntries);
}, []);

 console.log(person);