javascript - 循环访问对象时出错

Question

我有一个对象，比如说项目，我试图循环访问这个对象，但遇到了这个错误“无法将未定义或 null 转换为对象。

let items = {
  id: 1,
  name: "name1",
  currency: "usd"
}
const result = Object.keys(items).map(index => index.name);
console.log(result);

Answer 1

如果您想获取 key ，请使用Object.keys。值，Object.values:

let items = {
  id: 1,
  name: "name1",
  currency: "usd"
};
const keys = Object.keys(items);
const vals = Object.values(items);
console.log(keys);
console.log(vals);

.as-console-wrapper { max-height: 100% !important; top: auto; }

根据您当前的Object.keys代码，我认为您需要items[index]而不是index.name:

let items = {
  id: 1,
  name: "name1",
  currency: "usd"
}
const result = Object.keys(items).map(index => items[index]);
console.log(result);