为什么useState不更新数据？开发者社区

link管理

链接快照平台

输入网页链接，自动生成快照
标签化管理网页链接

文章/答案/技术大牛

发布

import React, { useState, useEffect, Component } from 'react'; 
import axios from 'axios'
const tableData = () => {
    const [tableData, setTableData] = useState([]);
    const [columns, setColumns] = useState([])
    useEffect(() => {
        axios.get('http://localhost:4000/')
            .then((res) => {
                if (res.status === 200) {
                    if (res.data === 0) {
                        console.log("Something is wrong !!!");
                    } else {
                        const data = res.data['rows']
                        const columns = Object.keys(data[0])
                        console.log(columns)
                        setTableData(data)
                        setColumns(columns)
            }).catch(error => {
                console.log(error)
    }, [])
    return (
            {columns.map((columnName, index) => {
                const {name} = columnName;
                return (
                        <li key={index}>{ name }</li>
}

    import React, { useState, useEffect, Component } from "react";
    import axios from "axios";
    const tableData = () => {
      const [tableData, setTableData] = useState([]);
      const [columns, setColumns] = useState([]);
      const fetchDetails = () => {
        axios
          .get("http://localhost:4000/")
          .then((res) => {
            const data = res.data["rows"];
            const columns = Object.keys(data[0]);
            console.log(columns);
            setTableData(data);
            setColumns(columns);
          .catch((error) => {
            //dont need to check the status if any occurs it will come to this catch block
            console.log(error.message);
      useEffect(() => {
        fetchDetails();
      }, [columns]);
      return (
            {columns.map((columnName, index) => {
              const { name } = columnName;

问 为什么useState不更新数据？ EN

回答 2

Stack Overflow用户

Stack Overflow用户