如何从对象中提取多个键并打印输出

Question

如何从事件处理程序内的对象中打印多个键？

这是我代码的链接-https：//codesandbox.io/s/suspicious-hamilton-erkqv

在第35行上，我将其称为" x"对象的事件处理程序更改名称。我能够打印一个称为"名称"的密钥(x.Name(如何打印X对象的所有3个道具(名称，ID，类型(??

尝试将x转换为带有object.keys(x(的数组

 const ChangeName = x => {
    setvalue(x.name);
  };

  <div>{value}</div> // display the results

Answer 1

您的值不是一个数组，它是为什么不能使用地图方法的对象，这就是它的工作方式：

import React, { useState, useEffect } from "react";
import ReactDOM from "react-dom";
function App() {
  const [posts, setposts] = useState([]);
  const [value, setvalue] = useState("");
  useEffect(() => {
    const posts = [
      {
        id: 1,
        name: "Name 1",
        type: "Type 1"
      },
      {
        id: 2,
        name: "Name 2",
        type: "Type 2"
      },
      {
        id: 3,
        name: "Name 3",
        type: "Type 3"
      },
      {
        id: 4,
        name: "Name 4",
        type: "Type 4"
      }
    ];
    setposts(posts);
  }, []);
  const ChangeName = x => {
    setvalue(x);
  };
  return (
    <div>
      <ul>
        {posts.map(post => (
          <li key={post.id}>
            {post.name},{post.type}
            <button onClick={() => ChangeName(post)}>More Info</button>
          </li>
        ))}
      </ul>
      <div>
        {value.name}
        {value.id}
        {value.type}
      </div>
    </div>
  );
}
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);

Answer 2

运行代码：

import React, { useState, useEffect } from "react";
import ReactDOM from "react-dom";
function App() {
  const [posts, setposts] = useState([]);
  const [values, setvalue] = useState([]);
  useEffect(() => {
    const posts = [
      {
        id: 1,
        name: "Name 1",
        type: "Type 1"
      },
      {
        id: 2,
        name: "Name 2",
        type: "Type 2"
      },
      {
        id: 3,
        name: "Name 3",
        type: "Type 3"
      },
      {
        id: 4,
        name: "Name 4",
        type: "Type 4"
      }
    ];
    setposts(posts);
  }, []);
  const ChangeName = x => {
    console.log(Object.values(x));
    Object.values(x).map(k => setvalue(k));
  };
  return (
    <div>
      <ul>
        {posts.map(post => (
          <li key={post.id}>
            {post.name},{post.type}
            <button onClick={ChangeName.bind(this, post)}>More Info</button>
          </li>
        ))}
      </ul>
      <div>{values}</div>
    </div>
  );
}
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);

您需要设置值而不是值。