Javascript useEffect缺少依赖项
就我的一生而言,我似乎无法删除关于我的useEffect缺少依赖项fetchProfile()的ESlinting警告。当我将fetchProfile添加到依赖项数组时,会得到一个无休止的循环。我非常感谢任何能帮助我压制这一警告的建议。代码如下:Javascript useEffect缺少依赖项,javascript,reactjs,react-hooks,Javascript,Reactjs,React Hooks,就我的一生而言,我似乎无法删除关于我的useEffect缺少依赖项fetchProfile()的ESlinting警告。当我将fetchProfile添加到依赖项数组时,会得到一个无休止的循环。我非常感谢任何能帮助我压制这一警告的建议。代码如下: import React, { useEffect, useContext, useReducer } from 'react' import { BrowserRouter as Router, Switch, Route } from 'react
import React, { useEffect, useContext, useReducer } from 'react'
import { BrowserRouter as Router, Switch, Route } from 'react-router-dom'
import './App.css'
import { MuiThemeProvider, createMuiTheme } from '@material-ui/core/styles/'
import UserContext from './contexts/UserContext'
import jwtDecode from 'jwt-decode'
import axios from 'axios'
// utils
import reducer from './utils/reducer'
import themeFile from './utils/theme'
import AuthRoute from './utils/AuthRoute'
import UnAuthRoute from './utils/UnAuthRoute'
// Components
import NavBar from './components/NavBar'
// Pages
import Home from './pages/Home'
import Login from './pages/Login'
import Profile from './pages/Profile'
import SignUp from './pages/SignUp'
import Admin from './pages/Admin'
import Dashboard from './pages/Dashboard'
import Alumni from './pages/Alumni'
// context
import { ProfileContext } from './contexts/ProfileContext'
const theme = createMuiTheme(themeFile)
// axios.defaults.baseURL = `https://us-central1-jobtracker-4f14f.cloudfunctions.net/api`
const App = () => {
const initialState = useContext(UserContext)
const [user, setUser] = useContext(ProfileContext)
const [state, dispatch] = useReducer(reducer, initialState)
const fetchProfile = async token => {
await axios
.get(`/user`, {
headers: {
Authorization: `${token}`
}
})
.then(res => {
setUser(res.data)
})
.catch(err => console.log({ err }))
}
// keeps userContext authorized if signed in
useEffect(
_ => {
const token = localStorage.FBIdToken
if (token && token !== 'Bearer undefined') {
const decodedToken = jwtDecode(token)
if (decodedToken.exp * 1000 < Date.now()) {
localStorage.removeItem('FBIdToken')
dispatch({ type: 'LOGOUT' })
} else {
dispatch({ type: 'LOGIN' })
state.isAuth && fetchProfile(token)
}
} else {
dispatch({ type: 'LOGOUT' })
localStorage.removeItem('FBIdToken')
}
},
[state.isAuth]
)
return (
<MuiThemeProvider theme={theme}>
<UserContext.Provider value={{ state, dispatch }}>
<div className="App">
<Router>
<NavBar isAuth={state.isAuth} />
<div className="container">
<Switch>
<Route exact path="/" component={Home} />
<UnAuthRoute
path="/signup"
component={SignUp}
isAuth={state.isAuth}
/>
<UnAuthRoute
path="/login"
component={Login}
isAuth={state.isAuth}
/>
<AuthRoute
path="/profile"
component={Profile}
isAuth={state.isAuth}
/>
<AuthRoute
path="/dashboard"
component={Dashboard}
isAuth={state.isAuth}
/>
<Route path="/admin" component={Admin} isAuth={state.isAuth} />
<AuthRoute
path="/users/:id"
component={Alumni}
isAuth={state.isAuth}
/>
</Switch>
</div>
</Router>
</div>
</UserContext.Provider>
</MuiThemeProvider>
)
}
export default App
import React,{useffect,useContext,useReducer}来自“React”
从“react Router dom”导入{BrowserRouter as Router,Switch,Route}
导入“./App.css”
从“@material ui/core/styles/”导入{MuiThemeProvider,createMuiTheme}”
从“./contexts/UserContext”导入UserContext
从“jwt decode”导入jwtDecode
从“axios”导入axios
//乌提尔斯
从“/utils/reducer”导入减速机
从“/utils/theme”导入主题文件
从“/utils/AuthRoute”导入AuthRoute
从“/utils/unauthorute”导入unauthorute
//组成部分
从“./components/NavBar”导入导航栏
//页数
从“./pages/Home”导入主页
从“./pages/Login”导入登录名
从“./pages/Profile”导入配置文件
从“./pages/SignUp”导入注册
从“./pages/Admin”导入管理员
从“./pages/Dashboard”导入仪表板
从“./页面/校友”导入校友
//上下文
从“./contexts/ProfileContext”导入{ProfileContext}
常量主题=CreateMuiteme(主题文件)
//axios.defaults.baseURL=`https://us-central1-jobtracker-4f14f.cloudfunctions.net/api`
常量应用=()=>{
const initialState=useContext(UserContext)
const[user,setUser]=useContext(ProfileContext)
const[state,dispatch]=useReducer(reducer,initialState)
const fetchProfile=异步令牌=>{
等待axios
.get(`/user`{
标题:{
授权:`${token}`
}
})
。然后(res=>{
setUser(res.data)
})
.catch(err=>console.log({err}))
}
//在登录时保持userContext的授权
使用效果(
_ => {
const token=localStorage.FBIdToken
if(令牌和令牌!==‘承载未定义’){
const decodedToken=jwtDecode(令牌)
如果(decodedToken.exp*1000
您可以执行以下两种操作之一:
fetchProfile
完全移出组件,并使用其结果,而不是让它直接调用setUser
fetchProfile
,这样只有当某项内容依赖于更改时,才能创建一个新的文件(这是…永远不会,因为fetchProfile
只依赖于setUser
,这是稳定的)。(您可能会使用或其近亲执行此操作,尽管理论上,usemo
[因此useCallback
]是为了性能增强,而不是“语义保证”。)const fetchProfile = token => {
return axios
.get(`/user`, {
headers: {
Authorization: `${token}`
}
})
}
然后
useffect(
_ => {
const token=localStorage.FBIdToken
if(令牌和令牌!==‘承载未定义’){
const decodedToken=jwtDecode(令牌)
如果(decodedToken.exp*1000setUser(res.data))//***
.catch(error=>console.error(error))//***
} // ***
}
}否则{
分派({type:'LOGOUT'})
localStorage.removeItem('FBIdToken')
}
},
[state.isAuth]
)
由于该操作是异步的,如果组件同时重新呈现,您可能希望取消/忽略它(这取决于您的用例)。您可以执行以下两种操作之一:
fetchProfile
完全移出组件,并使用其结果,而不是让它直接调用setUser
fetchProfile
,这样只有当某项内容依赖于更改时,才能创建一个新的文件(这是…永远不会,因为fetchProfile
只依赖于setUser
,这是稳定的)。(您可能会使用或其近亲执行此操作,尽管理论上,usemo
[因此useCallback
]是为了性能增强,而不是“语义保证”。)const fetchProfile = token => {
return axios
.get(`/user`, {
headers: {
Authorization: `${token}`
}
})
}
然后
useffect(
_ => {
const token=localStorage.FBIdToken
if(令牌和令牌!==‘承载未定义’){
const decodedToken=jwtDecode(令牌)
如果(decodedToken.exp*1000setUser(res.data))//***
.catch(error=>console.error(error))//***
} // ***
}
}否则{
分派({type:'LOGOUT'})
localStorage.removeItem('FBIdToken')
}
},
[state.isAuth]
)
由于该操作是异步的,如果组件在此期间重新呈现,您可能希望取消/忽略该操作(这取决于您的用例)。当您说将提取配置文件完全移出组件时