javascript - 创建一个名称字符串数组

Question

我想创建一个名称字符串数组

function namesOnly(arr) {

}
namesOnly([
  {
    name: "Angelina Jolie",
    age: 80
  },
  {
    name: "Eric Jones",
    age: 2
  },
  {
    name: "Paris Hilton",
    age: 5
  },
  {
    name: "Kayne West",
    age: 16
  },
  {
    name: "Bob Ziroll",
    age: 100
  }
])
// expect: ["Angelina Jolie", "Eric Jones", "Paris Hilton", "Kayne West", "Bob Ziroll"]

希望如此!

Answer 1

尝试使用 Array​.prototype​.map()

The map() method creates a new array with the results of calling a provided function on every element in the calling array.

function namesOnly(arr) {
  return arr.map(i => i.name);
}
var res = namesOnly([
  {
    name: "Angelina Jolie",
    age: 80
  },
  {
    name: "Eric Jones",
    age: 2
  },
  {
    name: "Paris Hilton",
    age: 5
  },
  {
    name: "Kayne West",
    age: 16
  },
  {
    name: "Bob Ziroll",
    age: 100
  }
])
console.log(res);

虽然我认为 map() 更适合这里，但您也可以使用 for...of 循环:

function namesOnly(arr) {
  var names = [];
  for (let o of arr) 
    names.push(o.name);
  return names;
}
var res = namesOnly([
  {
    name: "Angelina Jolie",
    age: 80
  },
  {
    name: "Eric Jones",
    age: 2
  },
  {
    name: "Paris Hilton",
    age: 5
  },
  {
    name: "Kayne West",
    age: 16
  },
  {
    name: "Bob Ziroll",
    age: 100
  }
])
console.log(res);