我遇到了动态生成不同类的对象实例的问题。所以我有一个服务器响应返回一个产品数组，这些产品的类型各不相同，因为要使用的实例化类以及传递给构造函数的参数会有所不同。
在下面的示例中，我有一个class Product根class Food扩展了classFurniture和constructors()这些扩展类的参数不同，需要在相对product.metaType中插入。
我正在使用产品属性class来保存有关//root product class which all inherit from
class Product{
constructor(price){
this.price = price;
this.quantity = null;
}
}
//food product class
class Food extends Product{
constructor(price,exp){
super(price);
this.expiration = exp;
}
}
//furniture product class
class Furniture extends Product{
constructor(price,dimensions){
this.price = price;
this.dimensions = dimensions;
}
}
class Chair extends Furniture{
constructor(price,dimensions,type){
super(price,dimensions);
this.type = type;
}
}
class Pizza extends Food{
constructor(price,exp,type){
super(price,exp);
this.type = type;
}
}
class Cookies extends Food{
constructor(price,exp,type){
super(price,exp);
this.type = type;
}
}
class IceCream extends Food{
constructor(price,exp,type){
super(price,exp);
this.type = type;
}
}
//init (iife)
(()=>{
//list of products emulated from a server response
var products:[
{
metaType: "Pizza",
name: "digiorno",
price: 20,
type: "pepperoni",
exp: new Date()
},
{
metaType: "Chair",
name: "Lazy Boy",
price: 400,
dimensions:{
height: 4,
width: 2,
length: 6
},
type: "modern"
},
{
metaType: "Cookies",
name: "Mrs. Fields",
price: 10,
type: "chocolate chip",
exp: new Date()
},
{
metaType: "IceCream",
name: "Ben & Jerry's",
price: 15,
type: "half baked",
exp: new Date()
}
];
var storeProducts = [];
//loop through products array
products.forEach((item)=>{
//create new instance of the specific product, append to the 'storeProducts' array
//each product contains a metaType property which is the CLASS to use
//how can I dynamically do this?
storeProducts.push(new window[item.metaType]());
});
})();在实例化中使用的信息。
uploadInfoTemplate = new InfoTemplate ({
title: "",
content: "<strong>Segment:</strong> ${segment}" +
"<hr/>" +
"<strong>Time:</strong> <i>${dateTime}</i>" +
"<div style='width: 100%; text-align:right;'>" +
"<input class='zoomButton' type='button' value='Zoom to' />" +
"</div>"
});
问题：如何动态实例化不同的类并传递参数？
答案 0 :(得分：0)
创建name -> constructor地图。 class es不会成为全局对象的属性：
const cls = {Food, Furniture, ...};
使构造函数接受单个参数并对其进行解构，例如
class Food extends Product{
constructor({price,exp}){
// ^ ^ destructuring
super(price);
this.expiration = exp;
}
}
然后你可以将整个对象传递给构造函数：
new cls[item.metaType](item);