javascript从数组中读取对象

Question

我如何读取列表中的玩家姓名？let Players = []let Player = {    sprite: 1,    coords: {M: 0, X: 0, Y: 0},    name: ""}function LoadPlayers(){console.log("total players: " + Players.length)let player1 = Playerplayer1.sprite = 0player1.coords = {M: 0, X: 6, Y: 1};player1.name = "jimpie"Players.push([player1]);let player2 = Player         player2.sprite = 0player2.coords =  {M: 0, X: 1, Y: 17};player2.name = "kolien"Players.push([player2]);console.log("total players: " + Players.length)console.log("Player 1 name: " + Players[1].name)console.log("Player 2 name: " + Players[0].name)}我现在得到“未定义”，我想从列表中的特定玩家读出玩家详细信息。

Answer 1

你有不同的错误。

首先，您必须使用new Player()而不仅仅是player.

其次，你应该使用这个：

Players.push(player1);

而不是这个：

Players.push([player1]);

第一个将 player1 推送到 Players 数组，第二个将仅包含 player1 的新数组推送到数组 Players。您还必须使用它来添加 player2。

Answer 2

这是因为您没有Player正确创建一个。而不是使用let player1 = Player，使用let player1 = new Player()。此外，您需要创建一个Players数组。最后，你需要Player上课。

class Player {

  constructor(sprite, coords, name) {

    this.sprite = sprite;

    this.coords = coords;

    this.name = name;

  }

}

var Players = []; // If you want to access this array

// from outside thefunction, keep it here. 

// Otherwise, move it in the LoadPlayers function

function LoadPlayers() {

  let player1 = new Player(0, {

    M: 0,

    X: 6,

    Y: 1

  }, "jimpie");

  Players.push(player1);

  let player2 = new Player(0, {

    M: 0,

    X: 1,

    Y: 17

  }, "kolien")

  Players.push(player2);

  console.log("total players: " + Players.length)

  console.log("Player 1 name: " + Players[0].name)

  console.log("Player 2 name: " + Players[1].name)

}

LoadPlayers();

Answer 3

function Player(sprite, coords, name){

    this.sprite = sprite;

    this.coords = coords;

    this.name = name;

}

let Players = []

function LoadPlayers(){

console.log("total players: " + Players.length)

let player1 = new Player(1, [32, 15, 14], "jimpie")

Players.push(player1);

let player2 = new Player(1, (1, 1, 1), "kolien")

Players.push(player2);

console.log("total players: " + Players.length)

console.log("Player 1 name: " + Players[0].coords)

console.log("Player 2 name: " + Players[1].name)

var allcoords = Players[0].coords

var xcoord = allcoords[1]

var ycoord = allcoords[2]

var mapnum = allcoords[0]

console.log("map: " + mapnum + " x: " + xcoord + " y: " + ycoord);

}

这很好用！