如何在javascript中将对象分配给类属性

Question

创建一个名为 Vending Machine (VM) 的类，它返回一个自动售货机的实例。 Vending Machine 实例包含一个inventory 属性，它是一个对象，其中包含库存物品的名称和每个物品的库存总量。

  drinkInventory = {
      1: { name: 'Sunny Delight', stock: 5 },
      2: { name: 'Diet Soda', stock: 3 },
      3: { name: 'Bottled Water', stock: 4 },
    };

class VM {
  constructor(obj) {
    this.iventory = Object.assign(this, obj);
  }
}

我正在尝试传入drinkInventory

Answer 1

更简单的是this.iventory = JSON.parse(JSON.stringify(obj))

 const drinkInventory= { 1: { name: 'Sunny Delight', stock: 5 } , 2: { name: 'Diet Soda', stock: 3 } , 3: { name: 'Bottled Water', stock: 4 } }; class VM { constructor(obj) { this.iventory = JSON.parse(JSON.stringify(obj)) } getStock(key) { return this.iventory[key].stock } } let bob = new VM(drinkInventory); drinkInventory['2'].stock = 50; console.log( 'bob stock 2 =', bob.getStock(2) );

您还可以使用 Spread 语法 => https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax

 const drinkInventory= { 1: { name: 'Sunny Delight', stock: 5 } , 2: { name: 'Diet Soda', stock: 3 } , 3: { name: 'Bottled Water', stock: 4 } }; class VM { constructor(obj) { this.iventory = { ...obj }; // then repeat copy for first level of object entanglement for (let elm in obj ) { this.iventory[elm] = { ...obj[elm] } } } getStock(key) { return this.iventory[key].stock } } let bob = new VM(drinkInventory); drinkInventory['2'].stock = 50; console.log( 'bob stock 2 =', bob.getStock(2) )