声明为现有数组不起作用

Question

在您阅读此代码并精疲力尽之前，请先了解它是一个名为 p5.js

的开源 JavaScript 库

我有基本包，没有附加包。看看这个...

var weapons = {
    //[WEAPON NAME]: [accuracy,repeat,recoil,recoilmax,recoil-recovery,damage,firerate,reloadspeed],
    M4A1: [10, 10, 0.2, 5, 1],

    //primary: weapons.M4A1,//ERROR
    //secondary: weapons.M4A1,//ERROR
    equipped: weapons.M4A1,
};

var inventory = {
  accuracy: weapons.M4A1[0],
  accuracyREF: 10,
  recoil: 0.2,
  recoilMAX: 3,
  recoilRecovery: 1,
  damage: 1,
  fireRate: 1,
};

显示空白屏幕，直到我删除声明 weapons.equipped

的行

我还尝试使用如下所示的 SPLICE p5.JS 语法同样适用于 arrayCopy()

var weapons = {
  //[WEAPON NAME]: [accuracy,repeat,recoil,recoilmax,recoil-recovery,damage,firerate,reloadspeed],
  M4A1: [10, 10, 0.2, 5, 1],

  //primary: weapons.M4A1,//ERROR
  //secondary: weapons.M4A1,//ERROR
  equipped: [0,0,0,0,0],
};

splice(weapons.M4A1, equipped, 0);

var inventory = {
  accuracy: weapons.M4A1[0],
  accuracyREF: 10,
  recoil: 0.2,
  recoilMAX: 3,
  recoilRecovery: 1,
  damage: 1,
  fireRate: 1,
};

这对我的游戏来说是必不可少的，如果做不到，我将不得不放弃它

Answer 1

var weapons 失败，因为您试图将其属性之一分配给自身，但它尚不存在。因此 var inventory 失败，因为 weapons 由于第一个错误而未定义。

要了解发生了什么，请从这里开始：

var weapons = {
  M4A1: [10, 10, 0.2, 5, 1],
  equipped: weapons.M4A1 // <-- weapons.M4A1 must be determined first
};
// weapons === undefined

在实例化var weapons之前，JS需要处理weapons.M4A1的值才能赋值给equipped。问题是 weapons 还不存在。

接下来您要尝试实例化 inventory。

// remember, weapons === undefined
var inventory = {
  accuracy: weapons.M4A1[0], // again, weapons.M4A1[0] must be determined
  accuracyREF: 10,
  ...
};
// inventory === undefined

...因此，inventory也无法实例化。

尝试 #2：splice(weapons.M4A1, equipped, 0);

p5/splice 声明 splice 适用于数组，而不适用于对象（以及您的实现的其他问题）。

你能做到吗？

var weapons = {
  M4A1: [10, 10, 0.2, 5, 1],
  equipped: [10, 10, 0.2, 5, 1]
};

var inventory = {
  accuracy: weapons.M4A1[0],
  ...
};

还是这个？

var weapons = {
  M4A1: [10, 10, 0.2, 5, 1],
  equipped: [0,0,0,0,0]
};
weapons.equipped = weapons.M4A1;

var inventory = {
  accuracy: weapons.M4A1[0],
  ...
};

Answer 2

使用 getter functions 的另一种解决方案。有关错误发生原因的解释，请查看@bloodyKnuckles 的回答。

var weapons = {
  //[WEAPON NAME]: [accuracy,repeat,recoil,recoilmax,recoil-recovery,damage,firerate,reloadspeed],
  M4A1: [10, 10, 0.2, 5, 1],
  get primary() {
    return weapons.M4A1
  },
  get secondary() {
    return weapons.M4A1
  },
  get equipped() {
    return weapons.M4A1
  },
};

var inventory = {
  accuracy: weapons.M4A1[0],
  accuracyREF: 10,
  recoil: 0.2,
  recoilMAX: 3,
  recoilRecovery: 1,
  damage: 1,
  fireRate: 1,
};

console.log("weapons", weapons);
console.log("inventory", inventory);

声明为现有数组不起作用

Declaring as an existing array doesn't work

javascript

processing

p5.js