javascript - 如何从Json数据中获取属性值

Question

我通过调用 Angular 中的 API 获取以下 Json 数据。

    {
"Product":[
    { "name":"Laptop", "sale":3000, "company":"hp", "date":"12 Oct"},
    { "name":"Mouse", "sale":300, "company":"lenovo", "date":"13 Oct"},
    { "name":"Laptop", "sale":5000, "company":"dell", "date":"12 Oct"},
    { "name":"Printer", "sale":4000, "company":"lenovo", "date":"14 Oct"},
    ]
}

我们如何将上面的 JSON 数据转换为下面的 key:value 格式。这里的 key 是产品名称，value 是该产品的总销售额。

{Laptop:8000,mouse:300,Printer:4000}

Answer 1

您可以使用Object.keys，如下所示:

result = {};
items = {
  Product: [
    { name: "Laptop", sale: 3000, company: "hp", date: "12 Oct" },
    { name: "Mouse", sale: 300, company: "lenovo", date: "13 Oct" },
    { name: "Laptop", sale: 5000, company: "dell", date: "12 Oct" },
    { name: "Printer", sale: 4000, company: "lenovo", date: "14 Oct" }
  ]
};

 ngOnInit(): void {
   Object.keys(this.items.Product).map(key => {
     const name = this.items.Product[key].name;
     const sale = this.items.Product[key].sale;
     if (this.result.hasOwnProperty(name)) {
       this.result[name] = this.result[name] + sale;
     } else {
       this.result[name] = sale;
     }
   });
   console.log(this.result); // { "Laptop": 8000, "Mouse": 300, "Printer": 4000 }
 }

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