Javascript 从api获取数据后,是否在React中显示嵌套对象?
json占位符中的用户数据将地址作为用户对象中的一个对象,我正试图弄清楚如何显示该数据以供学习和理解Javascript 从api获取数据后,是否在React中显示嵌套对象?,javascript,json,reactjs,object,Javascript,Json,Reactjs,Object,json占位符中的用户数据将地址作为用户对象中的一个对象,我正试图弄清楚如何显示该数据以供学习和理解 import React, { useState, useEffect } from "react"; import "./App.css"; const App = () => { const [users, setUsers] = useState([]); const [user, setUser] = useState({}); useEffect(() =>
import React, { useState, useEffect } from "react";
import "./App.css";
const App = () => {
const [users, setUsers] = useState([]);
const [user, setUser] = useState({});
useEffect(() => {
getUsers();
getUser();
//eslint-disable-next-line
}, []);
const getUsers = async () => {
const res = await fetch("https://jsonplaceholder.typicode.com/users");
const data = await res.json();
setUsers(data);
};
const getUser = async () => {
const res = await fetch("https://jsonplaceholder.typicode.com/users/1");
const data = await res.json();
setUser(data);
console.log(data);
};
return (
<div className="App">
<h3 style={{ marginBottom: "5px" }}>
Getting an Array of users from an Api
</h3>
<ul>
{users.map(user => (
<li style={{ marginBottom: "5px", paddingLeft: "10px" }}>
Name:{user.name} <br />
Email:{user.email}
</li>
))}
</ul>
<div className="card" style={{ width: "400px" }}>
<h3>Name: {user.name}</h3>
<p>Email: {user.email}</p>
</div>
</div>
);
};
export default App;
import React,{useState,useffect}来自“React”;
导入“/App.css”;
常量应用=()=>{
const[users,setUsers]=useState([]);
const[user,setUser]=useState({});
useffect(()=>{
getUsers();
getUser();
//eslint禁用下一行
}, []);
const getUsers=async()=>{
const res=等待获取(“https://jsonplaceholder.typicode.com/users");
const data=wait res.json();
设置用户(数据);
};
const getUser=async()=>{
const res=等待获取(“https://jsonplaceholder.typicode.com/users/1");
const data=wait res.json();
设置用户(数据);
控制台日志(数据);
};
返回(
从Api获取用户数组
{users.map(user=>(
-
名称:{user.Name}
电子邮件:{user.Email}
))}
名称:{user.Name}
电子邮件:{user.Email}
);
};
导出默认应用程序;
在这一点上,一切都很好
当我试图访问用户地址时,它会抛出一个错误
<div className="card" style={{ width: "400px" }}>
<h3>Name: {user.name}</h3>
<p>Email: {user.email}</p>
<p>Address: {user.address.street}
</div>
名称:{user.Name}
电子邮件:{user.Email}
地址:{user.Address.street}
如何访问对象中的对象和对象 您必须设置init user
因为呈现空值问题
const defaultUser = {
name: "",
email: "",
address: {
street: ""
}
};
const [users, setUsers] = useState([defaultUser]);
const [user, setUser] = useState(defaultUser);
您必须设置init user
因为呈现空值问题
const defaultUser = {
name: "",
email: "",
address: {
street: ""
}
};
const [users, setUsers] = useState([defaultUser]);
const [user, setUser] = useState(defaultUser);